🔋 — World-first direct observation of the charging mechanism of next-generation sodium-ion batteries via neutron scattering at J-PARC / 次世代ナトリウムイオン電池の充電メカニズムを世界初の直接観測（東北大／CROSS／東京理科大／横国大／Science Tokyo／JAEA／京大）
A research group led by Tohoku University (Y. Umemoto), CROSS (K. Ohishi), Tokyo University of Science (S. Komaba), Yokohama National University (R. Tatara), Science Tokyo (Y. Tateyama), JAEA/J-PARC (K. Hiroi, S. Takata) and Kyoto University (Y. Nambu) achieved the first real-time, multiscale direct observation of how sodium is stored in the hard-carbon anode of a next-generation sodium-ion battery. Using the "TAIKAN" small- and wide-angle neutron scattering instrument at J-PARC MLF, they performed operando measurements spanning length scales from ångström to ~100 nm and identified a three-step storage mechanism: adsorption at carbon surfaces/defects, intercalation between layers, and filling of nanoscale pores. The work supports the development of cheap, high-performance batteries based on abundant sodium.
An international group at RIKEN, the University of Tokyo and RMIT (T. Matsuura, H. Yamasaki, N. C. Menicucci) gave the first rigorous proof that fault-tolerant quantum computation is possible for continuous-variable (CV) optical quantum computing under general, realistic noise — not just the idealized random-displacement noise assumed in earlier work. They show that noise without strong spatial/temporal correlations can be translated into qubit-level errors correctable by existing quantum error-correcting codes, and that controlling the optical energy (keeping amplitudes bounded) is essential. The result clarifies the engineering requirements for photonic quantum computers, a field where Japan holds particular strength.
An international team including Nagoya University's Kobayashi–Maskawa Institute (KMI/IAR) with DESY, the University of Siegen and Karlsruhe Institute of Technology (KIT) proposed a strategy to search for physics beyond the Standard Model through ultra-precise measurements at a future electron–positron collider (FCC-ee). Focusing on the two-Higgs-doublet model (2HDM), they computed the process e⁺e⁻ → Higgs + neutrinos at full next-to-leading-order (NLO) electroweak accuracy. They showed that even in the "alignment limit" — where the extra Higgs bosons become indistinguishable from the Standard-Model Higgs — quantum (loop) effects still shift the theoretical prediction by a few percent, a deviation detectable at FCC-ee. The work opens an indirect route to reveal new particles from tiny deviations in precision data rather than by directly producing them.
Related keywords: two-Higgs-doublet model, 2HDM, 2ヒッグス二重項模型, beyond the Standard Model, 標準模型を超える物理, electroweak corrections, 電弱補正, NLO, FCC-ee, future collider, 次世代加速器, Higgs boson, ヒッグス粒子, alignment limit, 整合限界, precision measurement, 精密測定, particle physics, 素粒子物理, Nagoya University KMI, 名古屋大学, DESY, KIT, Syuhei Iguro, 井黒就平, Physical Review Letters
⭐ — Photometric, polarimetric and spectroscopic monitoring reveals the eruptive behaviour of the young star IRAS 21204+4913 / 若い星IRAS 21204+4913の突発的増光を確認（モスクワ大コーカサス山岳天文台）
A group of Russian astronomers led by Marina Burlak of Moscow State University began monitoring the young star IRAS 21204+4913 with the Caucasian Mountain Observatory (CMO) from early December 2025, performing photometric, polarimetric and spectroscopic observations to clarify its nature. The results reveal the eruptive behaviour of this star. Young stellar objects (YSOs) are stars in the early stages of evolution — protostars and pre-main-sequence stars — usually observed embedded in dense molecular clumps rich in molecular gas and interstellar dust. Because accretion onto YSOs proceeds episodically, these objects can undergo accretion-driven outbursts, which astronomers conventionally divide into EX Lup-type (EXor) and FU Ori-type (FUor) events. The observations were published on the arXiv preprint server on 16 February 2026.
A RIKEN-led international team (T. Yokouchi, M. T. Birch, Y. Tokura, N. Nagaosa and collaborators at Durham University and ISIS) discovered that the deformation of a current-driven skyrmion lattice produces an emergent electric field that manifests as a circuit "reactance," which they named emergent reactance. Measured in micron-scale MnSi devices under AC current, the effect appears in the skyrmion-stabilizing field range and grows as the device shrinks. Because its sign can change with temperature and field, a single element could behave as both an inductor and a capacitor — a candidate principle for shrinking circuit components by tens of thousands of times, with skyrmions driven at far lower current density than helical or domain-wall systems.
🧲 — Diamond quantum sensors image inhomogeneous superconductivity in the nickelate high-Tc superconductor La3Ni2O7 / ダイヤモンド量子センサーでニッケル酸高温超伝導体の「不均一超伝導」を可視化（ハーバード大）
ハーバード大学のノーマン・ヤオ（Norman Y. Yao）教授らの研究グループは、加圧下で高温超伝導を示すニッケル酸化物（ニッケレート）La₃Ni₂O₇について、ダイヤモンド中の窒素–空孔（NV）中心を量子センサーとして用い、高圧下のマイスナー効果（反磁性応答）をマイクロメートル分解能で「面」として直接イメージングすることに成功した。ダイヤモンドアンビルセルに埋め込んだNV中心による光検出磁気共鳴（ODMR）で、超伝導応答が数µmスケールで強く不均一（フィラメント状）に分布する様子を可視化。同じ視野で局所的な応力（歪み）場と組成（化学量論）も同時にマッピングし、超伝導応答と空間的に相関させることで、超伝導を抑制・増強する支配的メカニズムを実験的に解明した。加圧下の物質機能を広視野かつ局所的に観測できる本手法は、新超伝導体の探索を加速させると期待される。Nature掲載。
A Harvard-led team (Prof. Norman Y. Yao and colleagues) used nitrogen–vacancy (NV) centers in diamond as quantum sensors to perform wide-field, high-pressure optically detected magnetic resonance imaging of the local Meissner (diamagnetic) response in the pressurized nickelate superconductor La₃Ni₂O₇. The maps reveal that the functional superconducting response is strongly inhomogeneous (“filamentary”) at the few-micron scale. By simultaneously imaging the local stress field and stoichiometry in the same field of view and correlating them with the diamagnetic response, the team identified the dominant mechanisms that suppress and enhance superconductivity — a technique that should accelerate the search for new superconductors.
💎 — A quantum network of silicon-vacancy centers in diamond demonstrates non-local optical phase measurement — toward beating telescope-interferometer limits with entanglement / ダイヤ中シリコン欠陥（SiV）量子ネットワークで「非局所」光位相計測を実証 ～量子もつれで望遠鏡干渉計の限界突破へ～（ハーバード大）
ハーバード大学のM. D. ルーキン教授ら（筆頭著者 P.-J. スタス、Y.-C. ウェイら）は、ダイヤモンドのナノ光共振器に埋め込んだシリコン欠陥（SiV）中心を量子メモリとして用いた量子ネットワークで、離れた2地点に届く微弱な光の位相差を「非局所的」に測定する原理実証に成功した。長基線の望遠鏡アレイなどでは、光子の量子ノイズと損失が感度を根本的に制限する。研究チームは、遠隔のもつれ生成、「どちらの経路を通ったか」の情報を消す光子モード消去、もつれを利用した非破壊の光子ヘラルド（検出予告）を組み合わせ、量子もつれによってこの限界を超える新しい光センシングの可能性を示した。将来の大規模量子ネットワークや、量子強化型の天文干渉計につながる成果。Nature掲載。
A Harvard team (M. D. Lukin; first authors P.-J. Stas, Y.-C. Wei) used entangled quantum memories in a network of silicon-vacancy (SiV) centers in diamond nanocavities to perform a proof-of-concept non-local phase measurement of weak light arriving at two separate stations. The sensitivity of such non-local optical measurements—relevant to long-baseline telescope arrays—is fundamentally limited by quantum noise and photon loss. By combining event-ready remote entanglement, photon mode erasure that hides which-path information, and entanglement-enabled non-destructive photon heralding, the work shows how distributed entanglement can overcome these limits, pointing toward quantum-enhanced optical sensing and large-scale quantum networks. Published in Nature.
⚡ — Superconductivity controlled by a built-in light-confining cavity — vacuum fluctuations suppress it without any external light / 光をためる「空洞」で超伝導を制御 ～外部の光なしで真空のゆらぎが超伝導を抑制～（コロンビア大）
A team led by Itai Keren at Columbia University demonstrated for the first time that a material’s superconductivity can be altered simply by coupling it to a built-in light-confining cavity—without any external light, pressure or magnetic field. They interfaced hexagonal boron nitride (hBN), which hosts infrared hyperbolic modes, with the molecular superconductor κ-(BEDT-TTF)₂Cu[N(CN)₂]Br (κ-ET). When the hBN mode frequencies matched the C=C stretching vibration of κ-ET implicated in superconductivity, resonant coupling mediated by vacuum (quantum) fluctuations suppressed superconductivity in the adjacent crystal, confirmed by magnetic force microscopy and nano-optical measurements. The result advances “cavity materials engineering,” tuning quantum properties by design. Published in Nature (News & Views by A. Montanaro and D. Fausti).
🌌 — Largest ALMA image ever reveals the hidden chemistry of the Milky Way’s Central Molecular Zone (ACES survey) / アルマ望遠鏡史上最大の画像が天の川銀河中心「中心分子雲帯」の隠れた化学を解明 ～国際サーベイACES～（ESO／リヴァプール・ジョン・ムーアズ大／国立天文台ほか）
欧州南天天文台（ESO）は、リヴァプール・ジョン・ムーアズ大学（英）のスティーヴン・ロングモア教授を研究代表（PI）とし、ESOのアシュリー・バーンズ氏、コネチカット大学のカーラ・バタースビー氏、国立天文台（NAOJ）の謝佩穎（Pei-Ying Hsieh）氏、上海天文台の呂行（Xing Lu）氏ら、世界70以上の機関から160人超が参加する国際サーベイ「ACES（ALMA Central Molecular Zone Exploration Survey）」の成果を発表した。アルマ望遠鏡（ALMA）史上最大となるモザイク画像（見かけの大きさは満月3個分、実スケールで650光年超）により、超大質量ブラックホール「いて座A*」を取り囲む「中心分子雲帯（CMZ）」の低温分子ガス全域を、数十光年規模の大構造から個々の星を包む小さなガス雲までかつてない詳細さで初めて描き出した。一酸化ケイ素（SiO）のような単純な分子から、メタノール・アセトン・エタノールといった複雑な有機分子まで数十種を検出し、フィラメント状に流れる冷たいガスが塊へと集積して星を育む「銀河で最も極限的な星形成現場」の化学を明らかにした。CMZは初期宇宙の銀河に似たカオス的環境とされ、極限環境での星形成理論の検証や銀河進化の理解に道を開く。成果はMNRAS誌に受理された5本の論文（＋最終査読中の1本）として発表され、データはALMAサイエンスポータルで公開されている。
ESO announced results from ACES — the ALMA Central Molecular Zone Exploration Survey — led by PI Steven Longmore (Liverpool John Moores University) with over 160 scientists at more than 70 institutions, including ESO’s Ashley Barnes, UConn’s Cara Battersby, NAOJ’s Pei-Ying Hsieh and SHAO’s Xing Lu. The largest ALMA image ever made — a mosaic as long as three full Moons on the sky, spanning more than 650 light-years — maps the cold molecular gas across the entire Central Molecular Zone around Sgr A* for the first time in such detail, from structures tens of light-years across down to small clouds around individual stars. The survey detects dozens of molecules, from silicon monoxide to complex organics such as methanol, acetone and ethanol, tracing filaments of cold gas feeding the clumps where stars grow in the most extreme region of our galaxy — an environment thought to resemble star-forming galaxies in the early Universe. The results appear in five papers accepted by MNRAS (with a sixth in final review), and the data are public via the ALMA Science Portal.
Related keywords: ALMA, アルマ望遠鏡, ACES, Central Molecular Zone, 中心分子雲帯, CMZ, galactic centre, 銀河中心, Sagittarius A*, いて座A*, molecular filaments, 分子雲フィラメント, star formation, 星形成, methanol, メタノール, ethanol, エタノール, largest ALMA image, ESO, 欧州南天天文台, NAOJ, 国立天文台, Liverpool John Moores, Longmore, MNRAS
💎 — A robust, hydrogen-free telecom qubit identified in silicon: the "CN center" / シリコン中に頑健な通信波長量子ビット「CN中心」を同定（カリフォルニア大サンタバーバラ校）
The Computational Materials Group of Professor Chris Van de Walle at UC Santa Barbara identified a new candidate qubit in silicon, the "CN center." Qubits can be based on atomic-scale defects in a crystal, the prototype being the nitrogen-vacancy (NV) center in diamond. Recent attention has focused on the silicon T center, which stores quantum information for times comparable to the NV center and emits in the telecom band transmitted with low loss through optical fibre — but it is built from carbon and hydrogen, and hydrogen migrates easily within the crystal and is hard to control during processing, hampering reproducible fabrication. Using first-principles simulations, the team showed that the carbon–nitrogen CN center reproduces the electronic and optical properties that make the T center attractive — structural stability and telecom-range emission — while containing no hydrogen, making it more robust and easier to realize in actual devices. If confirmed experimentally, it could become a practical building block for quantum devices built on the same silicon that powers today's electronics. Published in Physical Review B.
Related keywords: qubit, 量子ビット, color center, カラーセンター, CN center, CN中心, T center, T中心, NV center, NV中心, silicon photonics, シリコンフォトニクス, telecom band, 通信波長帯, single photon emitter, 単一光子源, first-principles calculation, 第一原理計算, DFT, Physical Review B, UC Santa Barbara, Chris Van de Walle
大阪大学産業科学研究所の細貝知直教授（兼 理研放射光科学研究センターチームリーダー）、量子科学技術研究開発機構（QST）関西光量子科学研究所の神門正城所長、高エネルギー加速器研究機構（KEK）物質構造科学研究所の山本樹名誉教授らの研究グループは、レーザー航跡場加速（Laser Wakefield Acceleration；LWFA）で生成した電子ビームを用いて、極端紫外線（XUV）領域での自由電子レーザー（Free Electron Laser；FEL）の発振に世界で初めて成功した。LWFAはプラズマ中に生じる航跡波で電子を加速する方式で、従来の高周波加速器に比べて約1000倍という極めて大きな加速力（加速勾配）を持つ。これにより、これまで数十～数百メートル級の施設を要した高エネルギー加速器やX線・XUV光源を「卓上サイズ」へ小型化できる可能性があり、本成果はコンパクトで高輝度な次世代光源の実現に向けた重要なマイルストーンと位置づけられる。
A group led by Osaka University (Prof. Tomonao Hosokai, also a RIKEN team leader), QST (Director Masaki Kando) and KEK (Prof. Emeritus Shigeru Yamamoto) achieved free-electron laser (FEL) oscillation in the extreme-ultraviolet (XUV) range using an electron beam from laser wakefield acceleration (LWFA). LWFA accelerates electrons on the wake wave in a plasma and offers an accelerating gradient roughly 1,000 times that of conventional RF accelerators, raising the prospect of shrinking large accelerator and short-wavelength light-source facilities to tabletop scale — a milestone toward compact, high-brightness next-generation light sources.
Related keywords: laser wakefield acceleration, レーザー航跡場加速, LWFA, plasma acceleration, プラズマ加速, free electron laser, 自由電子レーザー, FEL, XUV, 極端紫外線, 加速器物理, 卓上加速器, Osaka University, 大阪大学, QST, KEK, RIKEN
🌌 — “Stochastic sirens”: a new way to measure the Hubble constant from the gravitational-wave background — toward resolving the Hubble tension / 重力波の「背景のうなり」でハッブル定数を測る新手法「確率的サイレン」（イリノイ大／シカゴ大）
Astrophysicists at the University of Illinois Urbana-Champaign (Grainger College of Engineering) and the University of Chicago — led by Bryce Cousins with Profs. Nicolás Yunes and Daniel Holz — introduced a new way to measure the Hubble constant from the faint “hum” of the stochastic gravitational-wave background produced by countless merging black-hole binaries, a technique they call the “stochastic siren.” Unlike standard-siren methods that rely on individually resolved mergers, this approach exploits the statistics of the unresolved background and improves the accuracy of gravitational-wave inferences of the Hubble constant. As LIGO–Virgo–KAGRA (LVK) detectors grow more sensitive, the method could help resolve the Hubble tension.
Related keywords: Hubble constant, ハッブル定数, Hubble tension, ハッブル・テンション, gravitational-wave background, 重力波背景, stochastic siren, 確率的サイレン, standard siren, 標準サイレン, LIGO, Virgo, KAGRA, LVK, cosmology, 宇宙論, expansion of the universe, 宇宙膨張, University of Illinois, University of Chicago, Nicolás Yunes, Daniel Holz
🤖 — A transformer language model "meta-designs" quantum-optics experiments, writing human-readable Python code that generates whole families of setups / 言語モデルが量子光学実験を「メタ設計」 ～実験群を人間可読なPythonコードとして生成～（テュービンゲン大／マックス・プランク光科学研究所）
An international team led by Mario Krenn (University of Tübingen; also Artificial Scientist Lab, Max Planck Institute for the Science of Light) with first author Sören Arlt developed a transformer-based language model that generates not single quantum-optics experiments but whole families ("classes") of setups with similar outputs. Trained on millions of quantum states and their experimental blueprints, the model infers general construction rules and writes human-readable Python code that, when run, designs many similar (and larger) experiments. Because the code is readable, scientists can extract the general design principles and extrapolate to larger experiments without further optimization — a strategy the authors call "meta-design." Published in Nature Machine Intelligence.
Related keywords: language model, 言語モデル, transformer, トランスフォーマー, meta-design, メタ設計, quantum optics experiment, 量子光学実験, AI for science, 科学のためのAI, Python code, Pythonコード, interpretability, 可読性, Mario Krenn, Sören Arlt, University of Tübingen, テュービンゲン大, Max Planck, Nature Machine Intelligence
⚙️ — Reversible, non-volatile ferroelectric control of 2D magnetism: interferroic magnetoelectric coupling at CuCrP₂S₆/Fe₃GeTe₂ van der Waals heterojunctions / 強誘電分極で2次元磁性を不揮発に制御（Nature Electronics）
Conventional electronics processes information using the electric charge of electrons; spintronic devices instead exploit the electron's spin, promising lower power, faster operation and easier miniaturization — which makes controlling magnetism without wasting power a central objective. Two-dimensional materials combining ferroelectric and ferromagnetic orders are attractive but fragile: depolarization fields destabilize ferroelectric order and thermal fluctuations suppress magnetic order. A group including Shanchuan Liang and corresponding author Cheng Gong built multiferroic van der Waals heterostructures from atomic layers of ferroelectric CuCrP₂S₆ and ferromagnetic Fe₃GeTe₂, demonstrating reversible, non-volatile ferroelectric control of the magnetic anisotropy of two-dimensional Fe₃GeTe₂ and using it to probe the interferroic magnetoelectric coupling. Polarization switching of CuCrP₂S₆ changes the magnetic coercivity of a 3.8-nm-thick Fe₃GeTe₂ layer by about 14 mT at 153 K, with a control efficiency around 65%; the efficiency falls as the Fe₃GeTe₂ thickness grows because of the short screening length. Published in Nature Electronics.
A team of Indian astronomers investigated the ultraluminous X-ray pulsar designated X-8 in the galaxy NGC 4631, known as the Whale galaxy, obtaining essential information on the magnetic field evolution of this object. Ultraluminous X-ray sources (ULXs) are bright point sources whose X-ray emission exceeds the total multiwavelength output of a million suns; they are less luminous than active galactic nuclei but more consistently luminous than any known stellar process, and some are now known to be strongly magnetized neutron stars accreting at super-Eddington rates from a companion. The study finds that the maximum surface dipole magnetic field strength of the neutron star is about 30–200 trillion gauss, with the donor star mass estimated between 15 and 70 solar masses, and examines the picture of accretion-induced decay of the neutron star's magnetic field in this system. Published on arXiv on 16 February 2026.
Related keywords: ULX, 超高光度X線源, ultraluminous X-ray pulsar, X線パルサー, neutron star, 中性子星, magnetic field decay, 磁場減衰, accretion, 降着, super-Eddington, 超エディントン, NGC 4631, Whale galaxy, クジラ銀河, X-ray astronomy, X線天文学, arXiv
🔀 — A heralded high-dimensional two-photon entangling gate: a controlled-phase-flip gate on two four-dimensional (OAM) photonic qudits / 光子2個の高次元もつれゲートを実証 ～軌道角運動量で符号化した4次元クディット間の制御位相反転（CPF）ゲート～（ウィーン工科大／南京大学）
In an international collaboration, Nicolai Friis and Marcus Huber (TU Wien / IQOQI Vienna) designed, and the group of Hui-Tian Wang and Xi-Lin Wang at Nanjing University (China) implemented, a heralded entangling gate between two photonic qudits, each encoded in four states (a four-dimensional qudit): a controlled-phase-flip (CPF) gate. The photons are encoded in orbital angular momentum (OAM), and success of the gate is heralded by an accompanying measurement. Because qudits carry the same information with fewer particles than qubits, this improves the efficiency and stability of quantum operations; the demonstrated gate is as complex as at least 13 two-qubit entangling gates. Published in Nature Photonics.
🌈 — For the first time, light mimics the quantum Hall effect — quantized transverse Hall drift of photons demonstrated / 光が「量子ホール効果」を初めて再現 ～光子の量子化された横方向ホールドリフトを実証～（モントリオール大／東北大／トレント大）
A team led by Philippe St-Jean (Université de Montréal), together with Tomoki Ozawa (Tohoku University), Iacopo Carusotto (University of Trento) and colleagues, reported the first observation of a quantized transverse (Hall) drift of light — a photonic realization of the quantum Hall effect, a phenomenon that has earned three Nobel Prizes and underpins modern resistance and mass metrology. Because photons carry no electric charge and do not respond to magnetic fields, recreating the effect with light had seemed extraordinarily difficult. The team engineered a frequency-encoded photonic Chern insulator in which light drifts sideways in perfectly quantized steps, just as electrons do. Small departures from perfect quantization could serve as extremely sensitive probes of environmental disturbances, and the platform opens routes to robust topological photonic devices, metrology and resilient photonic quantum information processing. Published in Physical Review X (February 5, 2026).
An international team using NASA's Transiting Exoplanet Survey Satellite (TESS) discovered a new exoplanet orbiting the star TIC-65910228, also designated NGTS-38. The planet is slightly larger than Jupiter (about 1.08 Jupiter radii) and nearly five times more massive (about 4.78 Jupiter masses) — a "super-Jupiter" — on a comparatively long, warm orbit with a period of roughly 180 days. The host is a bright, metal-rich F6V–F7V star some 864 light years away, estimated at 2.2 billion years old, nearly twice the size of the Sun, with about 1.46 solar masses and an effective temperature of 6,310 K. TESS observed the star several times in recent years, and a single transit signal detected in December 2020 set the discovery in motion. Long-period transiting giants are rare and valuable because they constrain how giant planets migrate. Posted to arXiv on 13 February 2026.
🪐 — JWST maps the vertical structure of Uranus' ionosphere for the first time / ウェッブ望遠鏡、天王星の上層大気を初めて3次元的に描き出す（ESA／ノーサンブリア大）
ジェイムズ・ウェッブ宇宙望遠鏡（JWST）による観測から、天王星の上層大気が初めて3次元的にマッピングされた。研究チームは雲頂から高度5,000キロメートルに至るまでの温度分布と荷電粒子の分布を追跡し、輝くオーロラ帯と、予想外の「暗い」領域が、天王星の極端に傾いた磁場によって形づくられている様子をとらえた。観測は、ノーサンブリア大学のH. Melin氏を主任研究者とするJWST一般観測プログラム5073のデータに基づき、2025年1月19日にNIRSpec分光器の面分光ユニット（IFU）で天王星を15時間連続観測して取得された。自転軸も磁軸も大きく傾いた天王星では、磁気圏と大気の結合が太陽系のほかの惑星と大きく異なり、その立体構造の解明は氷惑星の理解に直結する。Geophysical Research Letters掲載。
For the first time, scientists have mapped Uranus' upper atmosphere in three dimensions with JWST, tracking temperatures and charged particles up to 5,000 km above the cloud tops. Webb's sharp vision revealed glowing auroral bands together with unexpected dark regions, both shaped by the planet's wildly tilted magnetic field. The findings are based on JWST General Observer programme 5073 (PI: H. Melin, Northumbria University, UK): on 19 January 2025 the team used the NIRSpec Integral Field Unit to observe Uranus continuously for 15 hours. Because both the spin axis and the magnetic axis of Uranus are strongly inclined, the coupling between its magnetosphere and atmosphere differs markedly from that of other planets, so resolving the vertical structure feeds directly into our understanding of ice giants. Published in Geophysical Research Letters.
Related keywords: Uranus, 天王星, ionosphere, 電離圏, upper atmosphere, 超高層大気, aurora, オーロラ, magnetosphere, 磁気圏, magnetic field tilt, 磁軸傾斜, JWST, ジェイムズ・ウェッブ宇宙望遠鏡, NIRSpec, IFU, 面分光, ice giant, 氷惑星, Geophysical Research Letters, ESA, Northumbria University
🧮 — High-precision nuclear-structure calculations realized on a quantum computer — a new era for nuclear-physics simulation / 量子コンピュータを用いた高精度原子核構造計算の実現（宇都宮大／理研／東京大学）
A team from Utsunomiya University, RIKEN and the University of Tokyo (S. Yoshida, K. Sato, T. Ogata, M. Kimura) used RIKEN's Quantinuum trapped-ion quantum computer "Reimei" to obtain high-precision ground-state energies of oxygen, calcium and nickel isotopes. Atomic nuclei are strongly interacting quantum many-body systems whose first-principles structure calculations scale exponentially on classical computers; the result shows quantum computers approaching practically useful accuracy for nuclear-structure simulation, marking a step toward a "new era" of nuclear-physics simulation.
A group led by the University of Tokyo's RCAST (Prof. Hidekazu Mimura, also a RIKEN team leader), RIKEN (Group Director Makina Yabashi) and JASRI (Haruhiko Ohashi) developed a high-speed X-ray diagnosis method for industrial metal machining such as cutting and electrical discharge machining (EDM). Using newly developed, highly penetrating bright 100 keV X-rays from SPring-8 (beamline BL05XU), they captured—for the first time in the world—how metal is removed inside a workpiece and how the tool vibrates, at a frame interval of 1/5000 second. Because 100 keV X-rays penetrate several millimeters of common industrial metals such as iron and copper, processes previously hidden inside coolant and metal can now be observed directly, including burr formation and EDM phenomena. With the upcoming SPring-8-II promising even higher spatial and temporal resolution, the technique is expected to extend to cutting, EDM, laser machining and 3D printing, accelerating Japan's world-leading machine-tool and tooling development.
🌊 — First quantification of how magnetic fields, neutrinos and ejecta shape the gravitational-wave “memory” of binary neutron star mergers / 連星中性子星合体の重力波「メモリー効果」に磁場・ニュートリノ・放出物質が与える影響を世界初定量化（イリノイ大／アテネ・アカデミー／バレンシア大／モントクレア州立大）
An international team from the University of Illinois Urbana-Champaign (Jamie Bamber, Stuart L. Shapiro), the Academy of Athens (Antonios Tsokaros), the University of València (Milton Ruiz, Fabrizio Venturi Piñas) and Montclair State University (Marc Favata, Matthew Karlson) used general-relativistic magnetohydrodynamic simulations including neutrinos, with several viable equations of state, to quantify — for the first time — how the neutron-star magnetic field, neutrino emission and ejected mass affect the linear and nonlinear displacement “memory” of binary neutron star mergers, a permanent spacetime distortion that has never yet been measured. The additional contributions from electromagnetic radiation, neutrinos and baryonic ejecta reach ~15% of the total memory for moderate fields and up to ~50% for extreme (magnetar-class) fields. The memory is most sensitive to the equation of state, binary mass and magnetic field; strongly magnetized mergers can even yield a smaller total memory than non-magnetized ones, and — unlike binary black holes — the memory keeps growing over the long emission timescales of fields, neutrinos and ejecta. The results show that magnetic fields and the equation of state must be included in future memory searches with detectors such as the Einstein Telescope and Cosmic Explorer. Published in Physical Review Letters.
Related keywords: gravitational wave memory, 重力波メモリー効果, displacement memory, 変位メモリー, binary neutron star merger, 連星中性子星合体, GRMHD, 一般相対論的磁気流体シミュレーション, neutrino emission, ニュートリノ放出, baryonic ejecta, バリオン性エジェクタ, magnetar-class magnetic field, マグネター級磁場, equation of state, 状態方程式, University of Illinois, イリノイ大, Tsokaros, Favata, Einstein Telescope, PRL
🧲 — Evidence for intrinsic spin-triplet superconductivity in NbRe — a “holy grail” for quantum technology / 超伝導合金NbReに「物質固有のスピン三重項超伝導」の証拠 ～量子技術の“聖杯”に前進～（ノルウェー科学技術大NTNU／サレルノ大）
Theorist Jacob Linder’s group at NTNU’s QuSpin research centre, working with experimentalists at the University of Salerno (C. Attanasio, C. Cirillo and colleagues), reported evidence that the noncentrosymmetric alloy NbRe behaves as an intrinsic spin-triplet superconductor, based on inverse spin-valve measurements. In ferromagnet/superconductor/ferromagnet stacks — where a naturally formed hematite (α-Fe₂O₃) surface oxide pins one magnetic layer — switching the magnetic configuration shifts the superconducting transition temperature the “wrong way” for a conventional singlet superconductor. The result is consistent with earlier hints of two superconducting gaps (point-contact spectroscopy, specific heat) and time-reversal-symmetry breaking (muon-spin rotation). Because triplet Cooper pairs carry spin, such a material could transport spin currents with zero resistance, enabling ultra-low-power spintronics and stable Majorana-based quantum computing. With a transition temperature near 7 K — far above the ~1 K of other triplet candidates — NbRe is also practically attractive. Published in Physical Review Letters and selected as an Editor’s Suggestion.
Related keywords: triplet superconductivity, スピン三重項超伝導, NbRe, ニオブ・レニウム合金, noncentrosymmetric superconductor, 空間反転対称性の破れた超伝導体, inverse spin-valve effect, 逆スピンバルブ効果, hematite, ヘマタイト, spintronics, スピントロニクス, spin current, スピン流, Majorana, マヨラナ粒子, NTNU, QuSpin, Jacob Linder, University of Salerno, サレルノ大, time-reversal symmetry breaking, 時間反転対称性の破れ, PRL
⏱️ — An entanglement-enhanced optical ion clock: an entangled pair of ions delivers unprecedented clock stability / もつれたイオン対で光時計の安定度を向上（ドイツ物理工学研究所 PTB）
A team led by Kai Dietze at PTB, the German national metrology institute, demonstrated unprecedented stability in an optical clock by replacing single atoms with an entangled pair of ions. Every clock works by counting oscillations of some reference frequency — the swinging pendulum of a clocktower, or the vibrations of an electrified quartz crystal — and timekeeping accuracy is directly tied to how reliable those oscillations are: a pendulum accrues noticeable variations in its swing, whereas vibrating quartz is far more reliable, making quartz clocks far more accurate. Optical clocks, which reference an atomic optical transition, are the most precise timekeepers built, but their stability is fundamentally limited by quantum projection noise in measurements of individual atoms. By entangling two ions the team suppressed the impact of this quantum noise, achieving greater stability for the same measurement time — an approach the authors hope will usher in a new generation of optical clocks, opening new possibilities in precision experiments and metrology. Published in Physical Review Letters.
Every molecule has its own vibrational "fingerprint", reflecting both its chemical structure and its nanoscale surroundings, and infrared spectroscopy is one of the most powerful tools for reading it — but until now it has always been an ensemble technique. A team led by Assistant Professor Shaowei Li at UC San Diego introduced a measurement scheme that integrates frequency-tunable infrared excitation with scanning tunneling microscopy to characterize vibration-mediated nuclear motions of single molecules. They first validated the technique by monitoring the infrared-induced rotation of the ethynyl radical, then applied it to pyrrolidine on Cu(100), mapping its conformational dynamics. The resulting broadband spectra captured fundamental vibrational modes together with rich overtone and combination bands inaccessible by conventional methods, confirmed with isotopic substitutions. Density functional theory showed that delocalized modes coupled to pyrrolidine ring puckering drive the structural transition, revealing altered selection rules compared with traditional infrared spectroscopy. Published in Science.
A team at the Niels Bohr Institute, University of Copenhagen (Center for Quantum Devices and the Novo Nordisk Foundation Quantum Computing Programme; F. Berritta, M. Kjaergaard), together with NTNU, Leiden University and Chalmers, demonstrated a real-time adaptive measurement that tracks the fluctuating energy-relaxation rate (1/T1, the rate at which a qubit loses quantum information) of a superconducting qubit on millisecond timescales. Standard characterization takes seconds to minutes and averages out fast fluctuations; using an FPGA controller and adaptive Bayesian estimation, the method updates the relaxation rate close to the intrinsic timescale of the fluctuations themselves, revealing how a qubit switches between “good” and “bad” states. Built from commercially available hardware, the technique is a building block for calibrating, stabilizing and scaling quantum processors.
Related keywords: superconducting qubit, 超伝導量子ビット, energy relaxation rate, エネルギー緩和率, T1, real-time tracking, リアルタイム計測, FPGA, adaptive measurement, 適応計測, Bayesian, ベイズ推定, quantum computing, 量子コンピュータ, Niels Bohr Institute, ニールス・ボーア研究所, コペンハーゲン大学, Physical Review X
🌊 — Neutron-star tidal deformation described precisely in full general relativity — the new “relativistic and dynamical Love numbers” probe stellar interiors with gravitational waves / 中性子星の「潮汐変形」を一般相対論で精密記述 ～重力波で星の内部を探る新理論「相対論的・動的ラブ数」～（イリノイ大ほか）
A team led by Abhishek Hegade K. R. and Nicolás Yunes (University of Illinois Urbana-Champaign, with UC Santa Barbara, ICTS-Tata Institute and Montana State University) developed a theory describing, in full general relativity, how binary neutron stars tidally deform each other just before merger. They expand the dynamical tidal response in a complete set of stellar oscillation modes and show the mode amplitudes obey an effective forced-harmonic-oscillator equation, generalizing the Newtonian overlap-integral formulation. The relativistic treatment will reduce systematic biases in future gravitational-wave parameter estimation and help probe neutron-star interiors and dense matter. Published in Physical Review Letters as an Editors’ Suggestion.
Guido Burkard and Joris Kattemölle (University of Konstanz) showed that exploiting translational symmetry—recurring patterns in a quantum system—can cut the number of quantum gates needed for quantum simulation by several orders of magnitude. Because today’s quantum computers can run only a limited number of operations before errors accumulate, such efficiency is crucial. Using the simulation of 2D quantum electrodynamics (the Kogut–Susskind lattice model) as an example, they introduced a symmetry-based circuit-construction method (“QuanTile”) and benchmarked substantial savings over existing routing approaches—a practical technique even for mid-scale, pre-fault-tolerant machines. Published in Physical Review Letters.
A team from the Institute of Integrated Research at Institute of Science Tokyo (Assoc. Prof. Atsushi Shirane, graduate student Yasuto Narukiyo and colleagues) and KEK’s Institute of Particle and Nuclear Studies (Assoc. Prof. Masaya Miyahara) developed a 2.4 GHz Wi-Fi receiver chip that keeps operating under a cumulative radiation dose of 500 kGy — comparable to conditions inside a nuclear reactor, where ordinary wireless equipment can degrade within a short time. Built with a standard silicon CMOS process, the chip uses circuit techniques that dramatically enhance radiation hardness. Wireless in-reactor sensing and communication would make decommissioning work — including at Fukushima Daiichi — safer and more efficient, and the technology can extend to space, fusion reactors and accelerator instrumentation. Presented at ISSCC 2026, the premier international conference on solid-state circuits.
🌌 — Hubble, Euclid and Subaru uncover CDG-2, a galaxy that may be 99%+ dark matter, detected purely through its globular clusters / 「99%以上が暗黒物質」の銀河CDG-2を発見 ～球状星団だけで見つかった史上初の銀河～（トロント大／インスブルック大ほか）
トロント大学のDayi（David）Li博士研究員が率いる国際研究チームは、ハッブル宇宙望遠鏡・欧州宇宙機関（ESA）のユークリッド宇宙望遠鏡・すばる望遠鏡の観測データを組み合わせ、地球から約3億光年離れたペルセウス座銀河団の中に、質量のほぼすべてが暗黒物質（ダークマター）とみられる極めて暗い銀河「CDG-2（Candidate Dark Galaxy-2）」を発見した。CDG-2は通常の銀河のように星の光で見つかったのではなく、密集した4個の「球状星団」の存在から統計的に炙り出された、恒星の光ではなく球状星団のみによって検出された史上初の銀河である。ハッブルとユークリッドの画像から、4個の球状星団を取り巻く極めて淡い広がった光（銀河本体）が確認された。この銀河は太陽約600万個分の光しか放たず、質量の約99%（球状星団と暗黒物質ハローの関係を仮定すると最大99.9%以上）が暗黒物質と見積もられる。星形成に必要な水素ガスの多くは、銀河団内の他の銀河との重力相互作用で剥ぎ取られたと考えられる。球状星団を手がかりに「ほぼ見えない銀河」を探る手法の有効性を実証した成果。
An international team led by Dayi (David) Li (University of Toronto) combined data from the Hubble, ESA's Euclid, and the Subaru telescopes to identify CDG-2 (Candidate Dark Galaxy-2), an extremely faint galaxy in the Perseus cluster (~300 million light-years away) that appears to be almost entirely dark matter. Rather than being found by its starlight, CDG-2 was flagged statistically by a tight grouping of four globular clusters — making it the first galaxy detected purely through its globular-cluster population. Hubble and Euclid imaging revealed a faint diffuse glow around the clusters, confirming an underlying galaxy shining with the light of only ~6 million Suns. About 99% of its mass (up to ≳99.9% under standard globular-cluster–halo mass relations) is inferred to be dark matter, with most star-forming hydrogen gas likely stripped by interactions inside the dense cluster. The work demonstrates globular clusters as reliable tracers of nearly invisible, dark-matter-dominated galaxies.
Related keywords: dark galaxy, 暗黒銀河, dark matter, 暗黒物質, ダークマター, CDG-2, low surface brightness galaxy, 低表面輝度銀河, globular clusters, 球状星団, Perseus cluster, ペルセウス座銀河団, Hubble Space Telescope, ハッブル宇宙望遠鏡, Euclid, ユークリッド, Subaru Telescope, すばる望遠鏡, University of Toronto, トロント大, Dayi Li, Astrophysical Journal Letters, astrophysics, 天体物理
📡 — A 26,700-light-year radio jet uncovered in the barred spiral galaxy NGC 5938 (Araish) / 棒渦巻銀河に稀な大規模電波ジェットを検出（EMUサーベイ）
国際研究チームは、近傍の銀河NGC 5938（愛称「Araish」）の電波放射の起源を明らかにするため多波長観測を実施し、この銀河から約26,700光年にわたって広がる電波ジェットを検出した。強力な電波ジェットは、楕円銀河や大質量クェーサーではごく普通に観測される一方、渦巻銀河に存在する例は比較的まれであり、銀河の形態と中心ブラックホールの活動性の関係を考えるうえで貴重な事例となる。解析にはオーストラリアの電波望遠鏡ASKAPによるEMU（Evolutionary Map of the Universe）サーベイの高分解能画像および畳み込み画像、RACS（Rapid ASKAP Continuum Survey）のLow/Mid/High各バンド画像、さらに光学のDECaPS2 zバンド画像が用いられ、EMU高分解能画像の等高線を各パネルに重ね合わせて構造が調べられた（σ = 65 µJy/beam）。arXivに2月11日付で公開。
An international team of astronomers performed multi-wavelength observations of the nearby galaxy NGC 5938, nicknamed Araish, to investigate the origin of its radio emission, and detected an extended radio jet spanning about 26,700 light-years. Powerful radio jets are commonly seen in elliptical galaxies and massive quasars, but their presence in spiral galaxies is relatively rare, making this a valuable case for understanding how galaxy morphology relates to central black hole activity. The analysis used high-resolution and convolved images from the ASKAP EMU (Evolutionary Map of the Universe) survey, RACS Low, Mid and High band images, and a DECaPS2 optical z-band image, with EMU high-resolution contours overlaid at multiples of σ = 65 µJy/beam. Posted on arXiv on 11 February 2026.
Researchers at the U.S. Department of Energy's Oak Ridge National Laboratory (ORNL), working with partners in South Korea (University of Ulsan, Yonsei University, University of Seoul, Sungkyunkwan University), uncovered surprising behaviour in a specially engineered crystal of tantalum, tungsten and selenium. Ternary transition metal dichalcogenides (TMDs) provide a versatile platform for exploring novel electronic and magnetic ground states through compositional substitution and local structural modulation. Combining scanning tunnelling microscopy and spectroscopy (STM/S), magnetic property measurements and density functional theory (DFT), the team analysed how clustering of Ta atoms gives rise to local magnetic moments in TaWSe₂ single crystals. STM topography acquired at 4.5 K resolves triangular Ta clusters embedded within W-rich regions, with a consistent shape and orderly arrangement across the surface. DFT shows these clusters induce local strain that produces localized magnetic moments, and temperature-dependent magnetization exhibits a magnetic anomaly at about 50 K, corroborating the picture. Published in Advanced Functional Materials.
Related keywords: TaWSe2, ternary TMD, 三元系遷移金属ダイカルコゲナイド, transition metal dichalcogenide, atomic clustering, 原子クラスタリング, local magnetic moment, 局所磁気モーメント, STM, 走査型トンネル顕微鏡, STS, 走査トンネル分光, DFT, 密度汎関数理論, local strain, 局所歪み, quantum materials, 量子材料, Advanced Functional Materials, Oak Ridge National Laboratory, ORNL, University of Ulsan
⭐ — A double white dwarf binary discovered at the centre of the globular cluster NGC 6397 / 球状星団NGC 6397の中心部に白色矮星どうしの近接連星を発見（VLT/MUSE）
A team led by Fabian Göttgens used ESO's Very Large Telescope (VLT) to discover a compact binary system consisting of two white dwarfs, NF1 AB, at the centre of the nearby globular cluster NGC 6397. The analysis used a combined MUSE spectrum built from 19 individual spectra with a total exposure time of 4.2 hours. White dwarfs are the stellar cores left behind after a star has exhausted its nuclear fuel; their high surface gravity means their atmospheres are typically either pure hydrogen or pure helium, although a small fraction show traces of heavier elements. Double white dwarfs (DWDs) attract interest because their mergers are believed to produce new white dwarfs of higher mass — a channel relevant to type Ia supernovae and to space-based gravitational-wave detection. The dense cores of globular clusters are also natural sites where such compact binaries are formed and reshaped by dynamical interactions. Published on arXiv on 9 February 2026.
Related keywords: white dwarf, 白色矮星, double white dwarf, 二重白色矮星, binary star, 連星, globular cluster, 球状星団, NGC 6397, VLT, 超大型望遠鏡, MUSE, integral field spectroscopy, 面分光, type Ia supernova, Ia型超新星, stellar dynamics, 恒星力学, arXiv
🔦 — Quantum optical sensing techniques advance the pursuit of dark matter / 量子光センシングで暗黒物質探索の感度向上を目指す（米オークリッジ国立研究所）
Researchers at the U.S. Department of Energy's Oak Ridge National Laboratory are helping to pave a path toward the eventual discovery of dark matter. Because dark matter neither reflects, emits nor absorbs light, any signal its candidate particles leave in a detector is extremely faint and easily buried in instrumental noise. Bringing new approaches to measurement in the quantum realm and using quantum optical sensing techniques, ORNL scientists are developing the methods required to achieve "sight beyond sight" and detect this mysterious, invisible yet seemingly ubiquitous substance. Measurements exploiting engineered quantum states can surpass classical limits such as the standard quantum limit, making them particularly well suited to searches for light, wave-like dark matter candidates such as axions and dark photons. Published in Physical Review Research.
A team including Souvik Ghosh realized a "smart fluid" in which porous, anisotropically shaped colloidal particles dispersed in a nematic liquid crystal self-assemble into patterns that can be reversibly reconfigured with temperature. Colloidal dispersions — small particles suspended in a liquid — are behind everyday phenomena such as the whiteness of milk, which arises because the particles scatter light. When colloids are placed in a nematic liquid crystal, distortions of the molecular alignment around each particle (topological defects) mediate long-range elastic interactions, producing self-assembly quite unlike that in ordinary suspensions. By engineering the particles to be porous and anisotropic, the researchers gained control over these interactions and showed that the assembled structures can be switched by changing temperature — a design principle for soft matter whose optical and rheological properties respond to external stimuli. Published in Matter.
A team at QuTech, Delft University of Technology (L. P. Kouwenhoven) and CSIC Madrid (R. Aguado) achieved the first single-shot parity readout of the Majorana bound states at the ends of a “minimal Kitaev chain” built from two coupled semiconductor quantum dots—reading the even/odd parity in one measurement rather than by averaging. Majorana quasiparticles are their own antiparticles, and because the encoded information is spatially nonlocal, they could enable disturbance-resistant topological qubits. Demonstrating fast, non-destructive readout of information stored in Majorana states is a key milestone toward topological quantum computation.
🔬 — A compact tape-driven sample delivery system for serial femtosecond crystallography at SACLA cuts sample consumption by one to two orders of magnitude / XFEL施設SACLAで「テープ搬送式」試料導入システムを開発（理研／高輝度光科学研究センター／東北大／京大）
理化学研究所放射光科学研究センターの姜正敏研究員、矢橋牧名グループディレクター、高輝度光科学研究センター（JASRI）の登野健介チームリーダー、東北大学多元物質科学研究所の南後恵理子教授、京都大学大学院医学研究科の岩田想教授らの国際共同研究グループは、X線自由電子レーザー（XFEL）施設「SACLA」において、連続フェムト秒結晶構造解析（SFX）のための新しい試料導入システムを開発した。従来のSFXでは微小結晶を含む液体を連続的に流すため、間欠的にしか照射されないX線レーザーの合間に大量の試料が浪費されていた。新システムは厚さ約12マイクロメートルのポリイミドフィルムをコンベアベルトとして用い、ナノリットルスケールの液滴吐出装置2台を送り方向に直列配置。結晶を含む液滴と反応分子溶液の液滴をテープ上に重ねて吐出し、X線パルスのタイミングに同期させて照射位置まで運ぶ。テープ面をX線に垂直に配置したことで位置合わせが容易になり測定が安定した。混合時間は約0.1秒から20秒弱まで制御可能で、リゾチームとその阻害剤N-アセチルグルコサミンを用いた二液混合型の時分割SFXを実証、基質が活性部位に結合していく過程を原子レベルで捉えた。各データセットに必要なタンパク質はわずか1〜2 mgで、従来法の数十〜数百分の1にあたる。Journal of Applied Crystallography掲載（2月8日付）。
An international group from RIKEN SPring-8 Center (Jungmin Kang, Makina Yabashi), JASRI (Kensuke Tono), Tohoku University (Eriko Nango) and Kyoto University (So Iwata) developed a compact tape-driven sample delivery system for serial femtosecond crystallography (SFX) at the XFEL facility SACLA. Conventional SFX streams a continuous suspension of microcrystals, wasting most of the sample between the intermittent X-ray pulses. The new system uses a ~12 μm polyimide film as a conveyor belt, with two nanolitre-scale droplet dispensers arranged in series: droplets containing crystals and droplets of reactant solution are deposited on top of one another and carried to the interaction point in sync with the X-ray pulses, with the tape held perpendicular to the beam for easy and stable alignment. Mixing times are tunable from about 0.1 s to just under 20 s. In a two-droplet mixing time-resolved SFX demonstration with lysozyme and its inhibitor N-acetylglucosamine, the team followed substrate binding at the active site at atomic resolution using only 1–2 mg of protein per dataset — tens to hundreds of times less than conventional approaches. Published in Journal of Applied Crystallography (8 February 2026).
💻 — A silicon quantum processor detects single-qubit errors while preserving entanglement / シリコン量子プロセッサでもつれを壊さず単一量子ビットの誤りを検出（南方科技大／合肥国家実験室）
International Quantum Academy、南方科技大学（SUSTech）、合肥国家実験室の研究者らは、シリコンをベースとした量子プロセッサにおいて誤りを検出する新しい手法を開発した。量子誤り訂正・誤り検出では、量子情報そのものを直接読み出すと状態が壊れてしまうため、複数の量子ビットにまたがる「スタビライザー」と呼ばれる演算子だけを測定して誤りの痕跡（シンドローム）を取り出す必要がある。研究チームはこのスタビライザーに基づく誤り検出方式を小規模なシリコン量子プロセッサ上に実装し、個々の量子ビットに生じうるあらゆる種類の誤りを検出することを目指した。初期の試験では、提案手法がデコヒーレンス（およびそれに伴う情報の損失）を引き起こすことなく単一量子ビットレベルの誤りを検出できることが確認された。同時に、このシリコン量子計算システムでどの種類の誤りが最も多く発生しているのかを明らかにする手がかりも得られた。半導体産業の既存インフラを活用できるシリコンスピン量子ビットにおける、誤り耐性への一歩となる成果。Nature Electronics掲載。
Researchers at the International Quantum Academy, Southern University of Science and Technology (SUSTech) and Hefei National Laboratory developed a new approach to detecting errors in a silicon-based quantum processor. Because directly reading out quantum information destroys it, error detection relies on measuring multi-qubit "stabilizer" operators to extract error syndromes. The team implemented such a stabilizer-based error-detection scheme on their small processor, aiming to detect all possible types of errors affecting individual qubits. In initial tests the strategy successfully detected errors at the single-qubit level without causing decoherence and a consequent loss of information, while also shedding light on which errors are most prevalent in their silicon-based quantum computing system. The work is a step toward fault tolerance in silicon spin qubits, which can leverage existing semiconductor manufacturing infrastructure. Published in Nature Electronics.
Relativistic binary pulsars are among the best laboratories for testing general relativity in strong gravitational fields. Analysing long-term radio observations of the binary pulsar PSR J1906+0746, researchers refined the system parameters and obtained precise mass estimates of 1.316 M☉ for the pulsar and 1.297 M☉ for its companion. These values support the interpretation that this is a double neutron star system, although a massive white dwarf companion is not excluded. The analysis further identified a significant spin glitch — a sudden increase in the pulsar's rotation rate — and evidence for a possible planet-like third body with an orbital period of about 736 days and a mass of roughly 4 Earth masses. Because binary-pulsar mass measurements feed directly into the neutron-star equation of state and tests of gravity, follow-up observations are of considerable interest. Posted on arXiv.
Many technologies, such as sensors and batteries, rely heavily on electrochemical reactions, and improving them depends on understanding how those reactions work — yet most current methods cannot look at electrochemical reactions in detail. A team including Zhu Zhang developed "opto-iontronic microscopy", which optically reads out redox processes taking place inside a nanoscale hole, enabling optical voltammetry that follows electrochemical reactions millisecond by millisecond. A key advantage lies in the measurement conditions: an electron microscope, for instance, operates in high vacuum and therefore requires sample preparation, whereas opto-iontronic microscopy allows reactions to be studied under real working conditions with no sample preparation. Although its spatial resolution is currently lower than that of electron microscopy it remains high, and the technique measures every millisecond — advantages that also make it relatively inexpensive. Published in the Proceedings of the National Academy of Sciences.
⚡ — Strong correlations and superconductivity observed in a supermoiré lattice of mirror-symmetry-broken twisted trilayer graphene / 鏡映対称性を破ったねじれ三層グラフェンの「スーパーモアレ格子」に強相関と超伝導（EPFL）
A group led by Mitali Banerjee (corresponding author) with first author Zekang Zhou at EPFL set out to determine whether strong superconductivity can emerge in mirror-symmetry-broken twisted trilayer graphene (TTG). Working in the long-wavelength supermoiré lattice that arises from the interference of multiple moiré patterns, they performed systematic low-temperature transport measurements, tuning carrier density (gate voltage) and displacement field (top and back gates) to map out the phase diagram. "First, we measured its electrical resistance while carefully tuning two key parameters: the carrier density and the displacement field," explained Banerjee. Brown–Zak oscillations and Hofstadter's butterfly confirmed the supermoiré lattice and its mini-flat and mini-Dirac bands; the team observed isospin symmetry-broken phases within the mini-flat bands and a cascade of superconductor–insulator transitions enabled by the supermoiré lattice. High-quality hBN was supplied by Kenji Watanabe and Takashi Taniguchi of NIMS. Why robust superconductivity survives far from the magic angle remains an open question. Published in Nature Physics.
🌌 — A massive star in the Andromeda galaxy vanished after a 3-year infrared brightening — evidence for black-hole birth by direct collapse (no supernova) / アンドロメダ銀河の大質量星が3年間の赤外線増光の末に消失 ～超新星爆発を経ずに「直接崩壊」でブラックホール誕生の証拠～（米コロンビア大）
Kishalay De and colleagues at Columbia University identified a massive star (M31-2014-DS1) in the Andromeda galaxy (M31) that brightened in the infrared over ~3 years from around 2014, then abruptly faded and disappeared, leaving a shell of dust — using long-term infrared data from NASA's NEOWISE mission. They conclude it is strong evidence that the star collapsed directly into a black hole without a supernova explosion (a "direct collapse" or "failed supernova"), long anticipated as a common channel for black-hole formation but rarely observed convincingly. Published in Science.
Researchers at Kyushu University (Assoc. Prof. Sugumi Kanno and graduate student Akira Taniguchi) and Kobe University (Prof. Jiro Soda) achieved the first quantum-mechanical description of gravitational waves from binary black holes — a theoretical result. Evaluating the quantum state of the gravitons generated by the binary, they showed that the coherent-state description reproduces classical gravitational waves at leading order, while next-order effects generate squeezed states of gravitons; for GW150914 the squeezing parameter is estimated at ~10⁻⁴. This is not an observational detection of gravitons, but it theoretically identifies a tiny quantum component hidden in the waves — an important first step toward future tests of the graviton and quantum gravity.
🧲 — Full electronic structure of a cuprate high-Tc superconductor mapped, with evidence for electron “fractionalization” / 銅酸化物高温超伝導体の電子状態の全容解明と「電子の分裂」現象の証拠を発見（上智大／京大／理研／NIMS）
A collaboration of Sophia University (S. Sakai, M. Imada), NIMS (Y. Yamaji), Kyoto University (Y. Kohsaka) and RIKEN (T. Hanaguri) reconstructed, for the first time, the full energy- and momentum-resolved electronic structure of the cuprate high-Tc superconductor Bi2212 by jointly analysing complementary datasets (such as ARPES and scanning tunnelling spectroscopy). The analysis revealed evidence that the electrons are "fractionalized" into multiple degrees of freedom — a phenomenon at the heart of the decades-old puzzle of high-temperature superconductivity, offering an important clue to its mechanism.
🪐 — Evidence for “inside-out” planet formation around the red dwarf LHS 1903 from ESA’s CHEOPS / 赤色矮星LHS 1903に「内側から外側へ」進む惑星形成の証拠（ESA・CHEOPS）
欧州宇宙機関（ESA）の系外惑星特性評価衛星「CHEOPS（ケオプス）」による観測から、赤色矮星LHS 1903を周回する4惑星系で、最も内側と最も外側の惑星が岩石質である一方、中間の2惑星が膨らんだ（厚い）大気を持つという珍しい配置が明らかになった。標準的な惑星形成では内側ほど岩石的になると考えられてきたが、この配置は、惑星が原始惑星系円盤の内側から外側へ向かって順に形成される「インサイドアウト（inside-out／内側から外側へ）型」で、かつガスが枯渇した環境下で進む惑星形成モデルを支持する直接的な証拠とされる。T. G. Wilsonらによる成果で、Science誌に掲載された。
Using ESA's CHEOPS exoplanet characterisation telescope, T. G. Wilson and colleagues described an unusual configuration in the four-planet system around the red dwarf LHS 1903: the innermost and outermost planets are rocky, while the two middle planets have extended (puffy) atmospheres. The arrangement supports an "inside-out," gas-depleted planet-formation scenario in which planets form sequentially from the inner to the outer disk — published in Science.
Researchers at Iceberg Quantum proposed the "Pinnacle Architecture," a fault-tolerant quantum-computing design based on quantum low-density parity-check (qLDPC) codes. Under standard hardware assumptions, they estimate that a 2048-bit RSA integer could be factored with fewer than 100,000 physical qubits — about an order-of-magnitude reduction from earlier million-qubit estimates. The work sharply revises projections of the quantum resources needed to break RSA via Shor's algorithm, underscoring the urgency of migrating to post-quantum cryptography. (This is a non-peer-reviewed arXiv preprint.)
A team including Maxwell Gold at the Grainger College of Engineering, University of Illinois Urbana-Champaign, proposed a new protocol for building photonic graph states — multipartite entangled states of light — using quantum emitters that are inefficient. Graph states underpin measurement-based (one-way) quantum computation, quantum networks and fault-tolerant photonic quantum computing, and a leading route to producing them is to emit photons sequentially from a quantum emitter such as a quantum dot or colour centre. Real emitters, however, generate and out-couple photons with limited efficiency, and losing a photon partway through can destroy the entire graph state. The proposed scheme is "heralded": a separate measurement confirms that a photon was in fact produced, making the construction robust to emitter inefficiency and opening a path to photonic quantum computing and networking under realistic hardware conditions. Published in npj Quantum Information.
Related keywords: graph state, グラフ状態, photonic quantum computing, 光量子計算, measurement-based quantum computation, 測定型量子計算, cluster state, クラスター状態, quantum emitter, 量子エミッター, single photon source, 単一光子源, heralding, ヘラルド, quantum network, 量子ネットワーク, npj Quantum Information, University of Illinois
🔬 — Precision spectroscopy of atomic hydrogen pins down the proton radius and tests the Standard Model to 0.7 parts per trillion / 原子水素の精密分光で陽子半径を決定、標準模型を「0.7兆分の1」で検証（マックス・プランク量子光学研究所）
マックス・プランク量子光学研究所（MPQ、独ガルヒング）のローター・マイゼンバッハー（L. Maisenbacher）、ランドルフ・ポール（R. Pohl、マインツ大）、テオドール・ヘンシュ（T. W. Hänsch）、トーマス・ウーデム（Th. Udem）らの研究グループは、極低温の原子水素ビームをレーザー分光し、水素原子の2S–6P遷移周波数をν = 730,690,248,610.79(48) kHz という高精度で測定した。これにより陽子の電荷半径を r_p = 0.8406(15) fm と決定。従来の原子水素による測定より2.5倍以上高精度で、ミューオン水素から得られた値とも見事に一致し、長年の「陽子半径問題（proton radius puzzle）」を改めて収束させる結果となった。さらに、束縛状態の量子電磁力学（QED）を含む標準模型の予言と 0.7兆分の1（ppt）の精度で一致し、これは標準模型の最も精密な検証の一つとなった。keV領域の未知ボソンなど新物理への制約にも利用できる。Nature掲載。
A group at the Max Planck Institute of Quantum Optics (MPQ, Garching) — L. Maisenbacher, R. Pohl (Mainz), T. W. Hänsch and Th. Udem — measured the 2S–6P transition in a cryogenic beam of atomic hydrogen by laser spectroscopy, obtaining ν = 730,690,248,610.79(48) kHz and a proton charge radius r_p = 0.8406(15) fm. The value is at least 2.5× more precise than other atomic-hydrogen determinations and agrees with the muonic-hydrogen value, reinforcing the resolution of the long-standing “proton radius puzzle.” The result matches the Standard Model prediction to 0.7 parts per trillion — one of the most stringent tests of the SM (and of bound-state QED) to date — and can constrain new physics such as weakly interacting bosons in the keV range.
Related keywords: proton radius, 陽子半径, proton radius puzzle, 陽子半径問題, hydrogen spectroscopy, 水素分光, 2S-6P transition, quantum electrodynamics, 量子電磁力学, QED, Standard Model, 標準模型, precision measurement, 精密測定, muonic hydrogen, ミューオン水素, Max Planck Institute of Quantum Optics, MPQ, Hänsch, Udem, Nature
🧪 — Record-class coherence times in polyatomic-molecule qubits — a milestone for molecular quantum science using “parity-doublet” states / 多原子分子の量子ビットで世界最長級のコヒーレンス時間 ～「パリティ二重項」状態で分子量子科学に節目～（ハーバード大）
A Harvard team (J. M. Doyle; first author Paige Robichaud) optically trapped the triatomic molecule CaOH (calcium monohydroxide), prepared it in ℓ-type parity-doublet states, and achieved a bare qubit coherence time of T₂* = 0.8(2) s—longer than the 0.36 s lifetime of the bending mode and a milestone for storing quantum information in polyatomic molecules. Polyatomic molecules, with their rich internal structure, are promising for quantum information processing, quantum simulation and precision searches for physics beyond the Standard Model. The team suppressed differential Stark shifts by canceling ambient electric fields via molecular spectroscopy and characterized the parity-dependent trap shifts that limit coherence. Published in Nature.
🔷 — A familiar magnet gets stranger: a manifold of magnetic nodal lines found in elemental cobalt at room temperature / ありふれた強磁性体コバルトに「磁気ノーダルライン」の多様体を発見（ヘルムホルツ・センター・ベルリン／BESSY II）
An international team led by Dr Jaime Sánchez-Barriga at Helmholtz-Zentrum Berlin (HZB) uncovered complex topological features in the electronic structure of cobalt — an element normally regarded as a textbook ferromagnet with no further secrets. Spin-resolved angle-resolved photoemission (spin-ARPES) at the BESSY II synchrotron revealed entangled bands crossing each other along extended paths in specific crystallographic directions, forming a manifold of magnetic nodal lines that survives at room temperature. Fermi surfaces computed with density functional theory for a specific magnetic space group agree well with the measurements. Cobalt can therefore be regarded as a highly tunable and unexpectedly rich topological platform, opening new perspectives for exploiting magnetic topological states in future information technologies. Published in Communications Materials.
A team led by LMU Munich physicist Jochen Feldmann, together with the group of Zhi-Heng Loh at NTU Singapore, tracked for the first time the extremely brief formation of a polaron using ultrafast imaging. When an electron travels through a polar crystal its negative charge attracts the positively charged atomic cores, deforming the surrounding lattice; electron and lattice distortion then move together as a single object. The idea was published by Lev Landau in 1933 and formalized by Herbert Fröhlich in the 1950s, predicting that a cloud of phonons would make the electron lose energy and gain mass — "a bit like it has left a paved road and is wading through mud," as Feldmann puts it. The measurements used time-resolved photoemission electron microscopy at NTU: a first laser pulse excites an electron into the conduction band of BiOI nanoplatelets where it forms a polaron, and a second pulse ejects it, with flight time and exit angle giving the effective mass and energy. Over a million such events were needed; after a two-month campaign in Singapore and intensive analysis at LMU, the team found the effective mass doubled during the 160-femtosecond formation period, accompanied by a drop in energy — confirming that Fröhlich's formulas describe the process very well. Published in Physical Review Materials.
🔬 — NOvA delivers the most precise single-experiment constraint on the atmospheric neutrino mass splitting with 10 years of data / NOvA実験、10年分のデータでニュートリノ振動パラメータを高精度測定（米フェルミ研究所）
The NOvA experiment, based at Fermilab, reported precision neutrino-oscillation measurements using ten years of data. Neutrinos are neutral particles that rarely interact with matter; they come in three flavours (muon, electron, tau) and change flavour as they travel — neutrino oscillation — which requires that they have small but non-zero mass. NOvA observes this using the NuMI beam with two detectors about 800 km (500 miles) apart, one at Fermilab in Illinois and one in northern Minnesota. The new analysis uses double the neutrino-mode beam exposure of the previous one, with improved simulation and analysis techniques. A joint three-flavour fit to muon-neutrino disappearance, electron-neutrino appearance and the corresponding antineutrino channels yields the most precise single-experiment constraint on the atmospheric mass splitting, Δm²₃₂ = 2.431 +0.036/−0.034 × 10⁻³ eV² for normal ordering (−2.479 ± 0.036 × 10⁻³ eV² for inverted). Both orderings prefer a region close to maximal mixing with sin²θ₂₃ ≈ 0.55. The data mildly prefer the normal mass ordering with a Bayes factor of 2.4 (70% posterior probability), strengthening to 6.6 (87%) when a two-dimensional Δm²₃₂–sin²2θ₁₃ constraint from Daya Bay is included. Published in Physical Review Letters.
Astronomers from the National Astronomical Observatory of Japan (NAOJ) and elsewhere used the Subaru Telescope's Hyper Suprime-Cam to perform deep imaging of the distant globular cluster NGC 5466, yielding important information about the structure of the cluster's tidal stream. Stellar tidal streams arise from tidal interactions between a central galaxy and lower-mass systems such as satellite galaxies or globular clusters, and can retain the chemical and dynamical memory of their progenitors even after a few billion years — which makes them valuable probes of the Milky Way's mass distribution and of encounters with dark matter subhaloes. The observational footprint covers regions imaged in multiple bands and in g-band only, analysed relative to the cluster centre and its estimated tidal radius of 16.1 arcmin. Combining metallicity measurements using the NB395 narrow-band filter with an analysis of the mass function, the team argues that a gap seen in the stream may be intrinsic rather than an artefact of incomplete coverage. Posted on arXiv on 4 February 2026.
Related keywords: globular cluster, 球状星団, NGC 5466, tidal stream, 潮汐尾, 恒星流, Subaru Telescope, すばる望遠鏡, Hyper Suprime-Cam, HSC, NB395, metallicity, 金属量, mass function, 質量関数, dark matter subhalo, 暗黒物質サブハロー, Milky Way, 天の川銀河, NAOJ, 国立天文台, arXiv
🔀 — Universal "unusual magnetoresistance" traced to interfacial electron scattering rather than spin currents / 「異常磁気抵抗」の起源はスピン流ではなく界面電子散乱 ～スピントロニクスの標準的解釈に再考を迫る～（中国科学院半導体研究所／香港中文大学）
Prof. Lijun Zhu (Institute of Semiconductors, Chinese Academy of Sciences), Qianbiao Liu and Prof. Xiangrong Wang (Chinese University of Hong Kong) presented experimental evidence overturning the standard reading of the "unusual magnetoresistance" (UMR) that pervades spintronics. In UMR, the resistance of a heavy metal changes when it is placed next to a magnetic insulator and the magnetization is rotated in the plane perpendicular to the current — long attributed to magnetization-dependent interfacial reflection of a spin current (spin Hall magnetoresistance, SMR) and routinely used to extract spin-mixing conductance and spin-current parameters. Because similar signals appear in systems without strong spin Hall effects, and even in single-layer magnetic metals, competing models such as Rashba–Edelstein and orbital Hall magnetoresistance had proliferated. The new work shows that UMR arises from electron scattering at the interface, governed by two vectors — the interfacial magnetization and the electric field ("two-vector magnetoresistance") — with no spin current required, and reports very large UMR even in single-layer magnetic metals. It offers a unified framework for magnetoresistance across spintronic systems while calling SMR-based spin-current quantification into question. Published in National Science Review (online 11 June 2025).
Jupiter's moon Io is the most volcanically active body in the Solar System; its sulfur-dioxide-rich volcanic gas escapes to space and forms a dense ring of plasma along Io's orbit, the Io plasma torus (IPT). An international group led by graduate student Shinnosuke Satoh and Professor Fuminori Tsuchiya of Tohoku University, with Aix-Marseille Université, Keio University, Tohoku Institute of Technology and others, used ultraviolet auroral images from the Juno-UVS spectrograph aboard NASA's Juno spacecraft to measure the distorted structure of this torus. The key observable is the "lead angle": the longitudinal offset between Io's auroral footprint and the moon's true magnetic position. Because most of the Alfvén wave travel time is spent inside the dense torus, the lead angle inverts to the plasma conditions there. Ground-based telescopes cannot see the night side of the Jupiter system, but this approach covers the torus through all 360 degrees and so determines the true direction of the distortion without that limitation. The flux-tube mass content peaks at local time 03:42 and is minimum at 15:42, indicating the torus is distorted along that direction (uncertainty ±53 min); the electromagnetic force from the dawn–dusk electric field acts along the same direction, and comparison with earlier work shows the direction is not constant but evolves over long timescales. Published in The Planetary Science Journal.
Related keywords: Jupiter, 木星, Io, イオ, plasma torus, プラズマトーラス, Juno, Juno-UVS, aurora, オーロラ, auroral footprint, オーロラフットプリント, lead angle, リード角, Alfvén wave, アルヴェーン波, magnetosphere, 磁気圏, dawn-dusk electric field, 朝夕電場, ひさき, HISAKI, The Planetary Science Journal, 東北大学
⏱️ — The timescale of a quantum transition is set by crystal symmetry — measuring quantum time at the attosecond scale / 量子遷移の「時間スケール」は結晶の対称性で決まる ～アト秒で量子の時間を測る～（EPFL）
A group at EPFL (J. H. Dil) found that the time required for a quantum transition in a solid—on the attosecond scale—depends strongly on the crystal’s symmetry. Because an external clock disturbs such ultrafast quantum processes, the team instead used quantum interference, inferring the timescale from the relationship between accumulated phase and time. In three-dimensional copper the transition took about 26 attoseconds, whereas in the layered materials TiSe₂ and TiTe₂ it slowed to 140–175 attoseconds: the simpler and more low-dimensional the atomic structure, the longer the transition. The work bears on the foundational question of how time itself enters quantum mechanics.
Related keywords: quantum transition, 量子遷移, attosecond, アト秒, quantum timescale, 量子時間スケール, symmetry, 対称性, quantum interference, 量子干渉, TiSe2, TiTe2, copper, 銅, EPFL, スイス連邦工科大ローザンヌ校, foundations of quantum mechanics, 量子力学基礎, Newton
⚛️ — Energy release from the ⁹³ᵐMo nuclear isomer is triggered by inelastic nuclear scattering, not by nuclear excitation by electron capture / モリブデン93m核異性体のエネルギー放出機構を解明（中国科学院近代物理研究所）
中国科学院近代物理研究所（IMP）の丁兵氏らと、責任著者の一人である周小紅（Zhou Xiaohong）教授らの研究チームは、核異性体（アイソマー）である⁹³ᵐMo（モリブデン93m）が蓄えたエネルギーを放出する機構について、長年の論争に決着をつける実験結果を報告した。核異性体は原子核の準安定な励起状態で、長時間エネルギーを蓄えられるため「核電池」的な応用も議論されてきた。その脱励起（アイソマー・デプリーション）を人為的に引き起こす手段として有力視されてきたのが「電子捕獲による核励起（NEEC: nuclear excitation by electron capture）」で、自由電子が原子の空孔に捕獲される際に放出されるエネルギーで原子核が励起される過程である。今回の研究は、観測された⁹³ᵐMoの脱励起がNEECではなく非弾性核散乱によって引き起こされていることを示した。プラズマ中や天体環境、さらには慣性閉じ込め核融合における核異性体のふるまいを理解するための信頼できる実験データとなる。周教授によれば、NEEC自体は核異性体からのエネルギー放出を引き起こす方法として依然有望であり、今後はプラズマ環境や電子・イオンビーム衝突といった最適化された条件下での観測が必要になるという。Physical Review Letters掲載。
A team at the Institute of Modern Physics (IMP) of the Chinese Academy of Sciences, including corresponding author Prof. Zhou Xiaohong, settled a long-running debate over how the nuclear isomer ⁹³ᵐMo releases its stored energy. Nuclear isomers are metastable excited states of nuclei that can store energy for long times, motivating proposals for "nuclear batteries"; a leading candidate mechanism for triggering their depletion has been nuclear excitation by electron capture (NEEC), in which the energy released as a free electron is captured into an atomic vacancy excites the nucleus. The new measurements show that the observed depletion of ⁹³ᵐMo is triggered by inelastic nuclear scattering rather than NEEC. The result provides reliable experimental data for understanding isomer behaviour in plasmas, astrophysical environments and even inertial confinement fusion. According to Zhou, NEEC remains a promising route to triggering energy release from isomers, but future attempts to observe it may require optimized environments such as plasmas or electron–ion beam collisions. Published in Physical Review Letters.
Related keywords: nuclear isomer, 核異性体, アイソマー, isomer depletion, アイソマー・デプリーション, 93mMo, モリブデン93m, NEEC, 電子捕獲による核励起, inelastic nuclear scattering, 非弾性核散乱, nuclear physics, 原子核物理, plasma, プラズマ, inertial confinement fusion, 慣性閉じ込め核融合, Physical Review Letters, Institute of Modern Physics, 中国科学院近代物理研究所
❄️ — Heavy impurities in a Fermi gas described via a “mass gap” — a new picture for a long-standing quantum many-body problem / フェルミ気体中の「重い不純物」を質量ギャップで記述（ハイデルベルク大）
A group at Heidelberg University (R. Schmidt; doctoral candidate E. Dizer) offered a new picture in a long-standing debate over how a single impurity behaves when surrounded by a sea of fermions. The “Fermi polaron”—a composite quasiparticle formed as the impurity drags nearby particles along—is central to understanding strongly interacting systems from ultracold gases to solids and nuclear matter, but the heavy-impurity limit had resisted a clean description. By introducing a “mass-gap” description, the team captured heavy-impurity physics in a unified, rigorous way, with direct relevance to ongoing experiments in ultracold atomic gases, two-dimensional materials and novel semiconductors.
🌌 — The Milky Way’s central supermassive object may be a clump of dark matter — fermionic dark matter reproduces the S-star orbits / 天の川銀河中心の超大質量天体は暗黒物質の塊か ～フェルミオン暗黒物質でS星の軌道を再現～（英国王立天文学会）
アルゼンチン・ラプラタ天体物理研究所、ICRANet（国際相対論的天体物理ネットワーク）、ケルン大学などの国際研究グループは、天の川銀河の中心にある超大質量天体「いて座A*（Sgr A*）」が、必ずしもブラックホールではなく、フェルミオン（フェルミ統計に従う粒子）でできた高密度の暗黒物質の塊である可能性を示した。研究チームは、銀河中心を高速で公転する「S星」やガス雲「G天体」の軌道運動を、フェルミオン暗黒物質が自己重力でつくる天体モデルによって定量的に再現できることを示した。確立された「中心は超大質量ブラックホール」という描像に対する代替案を提示する成果で、今後さまざまな観測データとの比較による検証が求められる。Monthly Notices of the Royal Astronomical Society掲載。
An international team (Institute of Astrophysics La Plata, Argentina; ICRANet; University of Cologne, and others) argued that the supermassive object at the center of the Milky Way, Sagittarius A* (Sgr A*), need not be a black hole but could instead be a dense core of fermionic dark matter. The team quantitatively reproduced the orbital motion of the fast-moving “S-stars” and “G-sources” near the galactic center using a self-gravitating fermionic dark-matter model. The result offers an alternative to the standard black-hole picture and will need to be tested against a broad range of observations.
Related keywords: dark matter, 暗黒物質, fermionic dark matter, フェルミオン暗黒物質, Sagittarius A*, いて座A*, Sgr A*, supermassive black hole, 超大質量ブラックホール, galactic center, 銀河中心, S-stars, S星, G-sources, MNRAS, Royal Astronomical Society, 王立天文学会, ICRANet, cosmology, 宇宙論
🧲 — A previously unknown form of magnetism demonstrated in atomically thin layers: super-moiré spin textures in twisted 2D antiferromagnets / ねじれた2次元反強磁性体に「スーパーモアレ・スピン構造」を発見（シュツットガルト大ほか）
A group led by Professor Jörg Wrachtrup, head of the Center for Applied Quantum Technologies (ZAQuant) at the University of Stuttgart, working with international partners, experimentally demonstrated a previously unknown form of magnetism in atomically thin layers. Using twisted double-bilayer CrI₃, the team observed spin textures following a "super-moiré" periodicity — a superstructure on top of the twist-induced moiré lattice — and mapped how competing magnetic orders evolve within it. Beyond advancing the fundamental understanding of magnetic interactions in two-dimensional systems, the authors highlight direct relevance to next-generation magnetic data storage, where ever-growing data volumes demand reliable information storage at higher and higher densities. Published in Nature Nanotechnology.
Related keywords: moiré, モアレ, super-moiré, スーパーモアレ, twistronics, ツイストロニクス, antiferromagnet, 反強磁性, CrI3, 三ヨウ化クロム, 2D material, 二次元物質, van der Waals, ファンデルワールス, spin texture, スピン構造, magnetic storage, 磁気記録, Nature Nanotechnology, University of Stuttgart, ZAQuant, Jörg Wrachtrup
🌌 — JWST uncovers an unprecedented richness of hydrocarbons in the buried nucleus of a nearby ultra-luminous infrared galaxy / ウェッブ望遠鏡、超高光度赤外線銀河の「埋もれた核」に豊富な炭化水素を検出（CAB CSIC-INTA／オックスフォード大）
An international team led by Ismael García-Bernete of the Center for Astrobiology (CAB, CSIC-INTA), using modelling techniques developed at the University of Oxford, used JWST NIRSpec and MIRI/MRS spectroscopy (~3–28 μm) to reveal an unprecedented richness of small gas-phase hydrocarbons in the deeply obscured nucleus of the nearby ultra-luminous infrared galaxy IRAS 07251−0248. The nucleus is hidden behind vast amounts of gas and dust that absorb most of the radiation from the central supermassive black hole; infrared light penetrates the dust and exposes the dominant chemistry. The extragalactic detections include benzene (C₆H₆), triacetylene (C₆H₂), diacetylene (C₄H₂), acetylene (C₂H₂), methane (CH₄) and the methyl radical (CH₃) — the last never before seen outside the Milky Way — together with deep amorphous C–H absorption in the solid phase. The unexpectedly high abundances cannot be explained by high-temperature gas-phase chemistry, ice desorption or oxygen depletion; the most plausible explanation is erosion and fragmentation of carbonaceous grains and polycyclic aromatic hydrocarbons (PAHs).
⚛️ — STAR at RHIC finds spin correlations in Λ–Λ̄ pairs inherited from virtual quark pairs in the QCD vacuum / RHIC・STAR、QCD真空の仮想クォーク対に由来するΛ–反Λのスピン相関を発見 ～「無」から物質が生まれる量子真空をのぞく窓～（米ブルックヘブン国立研究所）
米エネルギー省ブルックヘブン国立研究所（BNL）の屠卓丹明（Zhoudunming "Kong" Tu）氏を共同研究代表とするSTARコラボレーションは、相対論的重イオン衝突型加速器（RHIC）の陽子・陽子衝突データを解析し、生成されたΛ（ラムダ）ハイペロンと反Λが近接して現れるとき、両者のスピンに相関があることを発見した。量子真空（何もない空間）は、実際には常にスピンの揃った仮想的なクォーク・反クォーク対を生成・消滅させている。RHICの高エネルギー衝突では、その一部が実在の粒子へと転化する。Λは崩壊時に放出する陽子（反Λは反陽子）の方向からスピンの向きを再構成でき、かつストレンジクォークを含むため真空由来かどうかを追跡しやすい。解析（筆頭 Jan Vanek、ニューハンプシャー大）の結果、近接するΛ–反Λ対の相対偏極は(18±4)%で、これはスピンが完全に揃った仮想ストレンジクォーク対（相関100%）を受け継いだ兆候と解釈される。QCDによるクォークの閉じ込め機構と、身の回りの物質の質量の起源に、新しい観測手段を与える成果。Nature掲載。
The STAR Collaboration at Brookhaven National Laboratory (co-led by Zhoudunming "Kong" Tu), analyzing proton–proton collisions at RHIC, found that Λ and anti-Λ hyperons produced close together have correlated spins. The quantum vacuum continually creates and annihilates spin-aligned virtual quark–antiquark pairs, and RHIC's energetic collisions turn some of them into real particles. A lambda's spin can be reconstructed from the emitted proton (antiproton for anti-Λ), and its strange quark helps trace a vacuum origin. The analysis (led by Jan Vanek, Univ. of New Hampshire) found a relative polarization of (18 ± 4)% for nearby Λ–Λ̄ pairs — interpreted as inherited from fully spin-correlated virtual strange quark–antiquark pairs in the QCD vacuum. The result offers a new probe of quark confinement and the origin of visible matter's mass. Published in Nature.
🔬 — STM/STS resolves two gaps and many-body resonances in magic-angle twisted trilayer graphene, linking the correlated normal state to superconductivity / 魔法角ねじれ三層グラフェンで超伝導と相関正常状態を結ぶ二つのギャップと多体共鳴を走査トンネル顕微鏡で分離（米カリフォルニア工科大ほか）
米カリフォルニア工科大学（Caltech）のS. ナジ＝ペルゲ（Stevan Nadj-Perge）教授のグループ（筆頭 H. キム）は、独ハンブルク大、米プリンストン大、独ゲーテ大フランクフルト、独ヴュルツブルク大、米UCサンタバーバラ、物質・材料研究機構（NIMS、渡邊賢司・谷口尚）らとの国際共同研究で、非従来型超伝導を示す「魔法角ねじれ三層グラフェン（MATTG）」を走査トンネル顕微鏡・分光（STM/STS）で調べ、フェルミ準位に固定された二つのギャップを分離して観測した。外側のギャップは高温・高磁場でも残る「擬ギャップ」に対応し、内側のギャップは超伝導と連動してより壊れやすい。動的な電子相関・谷間コヒーレンス・超伝導が織りなす相関相の形成過程を微視的に追跡することで、非従来型超伝導が高温の相関正常状態から立ち上がる仕組みに直接の手がかりを与えた。Nature掲載。
A team led by Stevan Nadj-Perge at Caltech (first author H. Kim), with international collaborators (Univ. Hamburg, Princeton, Goethe Univ. Frankfurt, Univ. Würzburg, UC Santa Barbara, and NIMS Japan — K. Watanabe & T. Taniguchi), used scanning tunneling microscopy/spectroscopy on magic-angle twisted trilayer graphene (MATTG) to resolve two gaps pinned at the Fermi level. The outer gap (a pseudogap) survives high temperatures and magnetic fields, while the newly revealed inner gap is more fragile and tracks superconductivity. Mapping how dynamic correlations, intervalley coherence and superconductivity build up the correlated phases gives a direct microscopic link between the correlated normal state and unconventional superconductivity. Published in Nature.
🕳️ — “The beacons were lit!” — NANOGrav’s first targeted continuous-wave searches for supermassive black hole binaries in 114 galaxies / 超大質量ブラックホール連星の「標的型」連続重力波探索を初実施 ～114個の活動銀河核から候補「ローハン」「ゴンドール」～（NANOGrav／イェール大）
NANOGrav — the North American Nanohertz Observatory for Gravitational Waves — led by corresponding author Chiara M. F. Mingarelli (Yale University), carried out the first targeted continuous-gravitational-wave searches for supermassive black hole binaries in 114 active galactic nuclei, using the NANOGrav 15-year pulsar-timing data set. Incorporating electromagnetic priors (sky position, distance, redshift and frequency) improves strain and chirp-mass upper limits by a median factor of 2.2 over all-sky limits. Bayesian analysis disfavors a signal for all targets (mean Bayes factor 0.73 ± 0.32); two targets — SDSS J1536+0441 (“Rohan”) and SDSS J0729+4008 (“Gondor”, both nicknamed after the beacon-lighting of The Lord of the Rings) — sit slightly above unity but are shown to be consistent with noise by coherence tests, random-targeting experiments and a conservative trials-factor accounting. They serve as worked examples of an end-to-end detection protocol, laying out a roadmap from the gravitational-wave background discovered in 2023 toward identifying individual binaries and ultimately mapping merging supermassive black holes across the Universe. Published in The Astrophysical Journal Letters.
🧊 — A topological superconductor tuned by electronic correlations in ultrathin Fe(Te,Se) films / 電子相関で「トポロジカル超伝導」をチューニング ～鉄テルル化セレン超薄膜のTe/Se比で量子相を制御～（シカゴ大／ウェストバージニア大）
A team at the University of Chicago Pritzker School of Molecular Engineering (S. Yang, H. Lin) and West Virginia University (S. Mandal) showed that a topological superconductor — a prized material for fault-tolerant quantum devices — can be tuned into existence simply by adjusting a material's chemical recipe. Using high-resolution laser ARPES on 10-unit-cell-thick MBE-grown iron telluride selenide, Fe(Te,Se), films, they found that varying the tellurium-to-selenium ratio changes the strength of electron correlations, driving the film between distinct quantum phases. Above ~70% tellurium the film develops topologically non-trivial surface states, but near pure FeTe the correlations grow so strong that the dxy-orbital-derived bands lose coherence and the topological surface state disappears. Electron correlation thus acts as a control "dial" for topological superconductivity, realized at a relatively high ~13 K, offering a practical route toward stable next-generation quantum devices.
Related keywords: topological superconductor, トポロジカル超伝導体, electronic correlations, 電子相関, iron telluride selenide, 鉄テルル化セレン, Fe(Te,Se), FeTeSe, thin film, 薄膜, MBE, laser ARPES, レーザーARPES, topological surface states, トポロジカル表面状態, quantum computing, 量子コンピュータ, condensed matter, 凝縮系物理, University of Chicago, シカゴ大, West Virginia University, Shuolong Yang, Nature Communications
🧮 — Lattice surgery demonstrated between two distance-three repetition codes on a superconducting processor / 超伝導量子ビットで「格子手術」を実現（ETHチューリッヒ／ユーリッヒ研究センター／アーヘン工科大）
A group led by Professor Andreas Wallraff at ETH Zurich, with Forschungszentrum Jülich (Institute for Theoretical Nanoelectronics, PGI-2) and RWTH Aachen University, demonstrated lattice surgery on a 17-qubit superconducting processor. Quantum error correction is needed for quantum computers to execute algorithms with hundreds of logical qubits fault-tolerantly, and recent experiments have achieved sufficiently low error rates for preserving a single logical qubit — but algorithms also require entangling logical qubits and performing gates on them. Lattice surgery offers a practical route to such gates, particularly for planar processor layouts. The team performed lattice surgery between two distance-three repetition-code qubits by splitting a single distance-three surface-code qubit, and using a circuit that is fault-tolerant for bit-flip errors they achieved an improvement in the decoded logical ZZ two-qubit observable compared with a similar non-encoded circuit — demonstrating the functional building blocks needed for lattice-surgery operations on larger-distance codes. Published in Nature Physics.
🔭 — JWST makes the first observation of planet-forming silicate crystallization around the protostar EC53 / 原始星EC53で惑星材料（ケイ酸塩）の結晶化をJWSTが初観測（理研／ソウル大／東京大学ほか）
An international group led by RIKEN (Yao-Lun Yang), Seoul National University (Jeong-Eun Lee) and the University of Tokyo (Yuri Aikawa) used JWST/MIRI to directly capture, for the first time, the crystallization of planet-forming silicate dust around the young protostar EC53 (~1,400 light-years away in Ophiuchus) triggered by an accretion burst. Comparing quiescent and burst phases, crystalline-silicate signatures (forsterite, enstatite) appeared only during the burst, and the crystals are carried outward by a nested magnetohydrodynamic (MHD) disk wind. The finding helps explain the long-standing puzzle of why comets formed in the cold outer disk contain high-temperature crystalline minerals. Published in Nature.
Related keywords: protostar, 原始星, EC53, JWST, James Webb Space Telescope, MIRI, accretion burst, アクリーション・バースト, silicate crystallization, ケイ酸塩結晶化, forsterite, フォルステライト, enstatite, エンスタタイト, protoplanetary disk, 原始惑星系円盤, MHD disk wind, comet, 彗星, 天体物理学, RIKEN, Seoul National University, 東京大学
💥 — The runaway star HD 254577 identified as the pre-supernova binary companion of the IC 443 progenitor / 超新星に吹き飛ばされた「暴走星」を特定（イェーナ大ほか）
大質量の「暴走星（runaway star）」は、もともと連星をなしていた相棒が超新星爆発を起こした際に劇的に宇宙空間へ放り出されたものだ——という長年の予測を、ドイツ・イェーナ大学のバハ・ディンチェル（Baha Dinçel）氏が率いる国際研究チームが観測と恒星モデルの組み合わせによって強く裏づけた。太陽を含む大半の星が周囲に対してゆっくりとしか動かないのに対し、暴走星は星間空間を毎秒数十〜数百キロメートルで駆け抜ける。研究チームは、最近の超新星が起きたことが確実で暴走星が近くにいるはずの超新星残骸（SNR）の内部を探索するという戦略をとり、SNR IC 443（くらげ星雲）の中に大質量星HD 254577を見いだした。分光観測から、この星は有効温度24,000±1,000 K、表面重力log g = 2.75±0.25のB0.5II型の高温かつ進化した星で、3次元固有速度は31.3 km/s、太陽からの距離は約1,701 pcと決定された。星のスペクトルに現れる高速の星間吸収線が青方偏移側のみに見えることは、この星がSNRの内部にあることを示す。固有運動の向きと、中性子星CXOU J61705.3+222127がもつ彗星状の尾は、両者が同じ「連星型超新星」に由来することを意味する。爆発は約1万〜3万年前と見積もられた。Astronomy & Astrophysics掲載。
A team led by Baha Dinçel at the University of Jena strengthened the long-standing prediction that massive runaway stars originate in binaries and are ejected when their companion explodes as a supernova. Most stars, including the Sun, move slowly relative to their neighbours, whereas runaway stars tear through interstellar space at tens to hundreds of kilometres per second. Searching inside supernova remnants — where a recent explosion is guaranteed and the runaway should still be nearby — the team identified the massive star HD 254577 within SNR IC 443, the Jellyfish nebula. Spectroscopy shows it to be a hot, evolved B0.5II star with an effective temperature of 24,000 ± 1,000 K and log g = 2.75 ± 0.25, a three-dimensional peculiar velocity of 31.3 km/s and a heliocentric distance of about 1,701 pc. High-velocity interstellar absorption lines shifted only to the blue place the star inside the remnant, and its proper motion together with the cometary tail of the neutron star CXOU J61705.3+222127 implies a common origin in a binary supernova, which occurred roughly 10,000–30,000 years ago. Published in Astronomy & Astrophysics.
Related keywords: runaway star, 暴走星, supernova remnant, 超新星残骸, IC 443, Jellyfish nebula, くらげ星雲, binary star, 連星, massive star, 大質量星, neutron star, 中性子星, pulsar kick, Gaia DR3, proper motion, 固有運動, spectroscopy, 分光観測, Astronomy & Astrophysics, University of Jena
🔬 — Graphene sealing enables the first atomic-resolution images of monolayer transition metal diiodides / グラフェン封止で単層遷移金属ジヨウ化物の原子分解能観察に初成功（マンチェスター大）
英マンチェスター大学 国立グラフェン研究所（NGI）の研究チームは、単層の遷移金属ジヨウ化物（transition metal diiodides）について、原子分解能でのイメージングに世界で初めて成功した。これらの二次元物質は磁性や電子物性の観点から興味を持たれてきたが、空気に触れるとわずか数秒で完全に壊れてしまうため、従来の作製手法では観察はおろか素子化すら困難だった。「これらの物質を扱うのは最初は不可能に思えた。数秒の大気曝露で完全に破壊されてしまい、従来の作製アプローチが使えない」と、転写技術の開発と試料作製を担当したWendong Wang博士は語る。研究チームは、結晶をグラフェンで完全に包み込んで封止した透過型電子顕微鏡（TEM）試料を作製することで劣化を防ぎ、原子レベルで清浄な界面を保ったまま、使用可能な寿命を数秒から大きく引き伸ばすことに成功した。新しい二次元磁性体・電子材料の探索を加速する試料作製技術となる。ACS Nano掲載。
Researchers at the National Graphene Institute of the University of Manchester achieved the first atomic-resolution imaging of monolayer transition metal diiodides. These two-dimensional crystals are of interest for their magnetic and electronic properties but degrade completely within seconds of contact with air, which has made conventional fabrication — let alone imaging — extremely difficult. "Working with these materials felt impossible at first as they are completely destroyed after a few seconds of air exposure, preventing traditional fabrication approaches," explained Dr Wendong Wang, who developed the transfer technique and fabricated the samples. By creating graphene-sealed TEM samples that fully encapsulate the crystals, the team prevented degradation, preserved atomically clean interfaces and extended the usable lifetime of the material far beyond a few seconds — a sample-preparation route that should accelerate the search for new 2D magnets and electronic materials. Published in ACS Nano.
Related keywords: 2D material, 二次元物質, transition metal diiodide, 遷移金属ジヨウ化物, graphene encapsulation, グラフェン封止, TEM, 透過型電子顕微鏡, atomic resolution, 原子分解能, air sensitivity, 大気不安定性, van der Waals, ファンデルワールス, ACS Nano, National Graphene Institute, University of Manchester
🕳️ — Exploding primordial black holes may explain the ultra-high-energy neutrinos seen by KM3NeT and IceCube / 原始ブラックホールの「爆発」が超高エネルギーニュートリノの謎を説明か（マサチューセッツ大アマースト校）
マサチューセッツ大学アマースト校のマイケル・ベイカー（Michael J. Baker）助教、ホアキム・イグアス・フアン、エイダン・サイモンズ、アンドレア・タムらの研究グループは、KM3NeTが2023年に観測した約100 PeV（ペタ電子ボルト）級の超高エネルギーニュートリノ事象（KM3-230213A）と、IceCubeが捉えた1 PeV超のニュートリノ5個を、「原始ブラックホール（PBH）の蒸発・爆発」で統一的に説明できる理論モデルを提案した。単純なシュワルツシルト型PBHでは、KM3NeTとIceCubeの観測頻度やガンマ線背景との間に矛盾が生じる。研究チームは、新たな「ダーク U(1)」電荷を帯び、ほぼ極限（quasi-extremal）状態で長く留まるPBHの集団を考えると、1 PeVでのニュートリノ放出が100 PeVより抑制され、両観測と諸制約が1σで整合することを示した。さらに、このダーク電荷PBHが宇宙の暗黒物質のすべてを構成しうるという。確認されればホーキング放射の検証や暗黒物質の正体解明にもつながる可能性がある。Physical Review Letters掲載。
A team at the University of Massachusetts Amherst (Michael J. Baker, Joaquim Iguaz Juan, Aidan Symons, Andrea Thamm) proposed that the ∼100 PeV ultra-high-energy neutrino seen by KM3NeT in 2023 (KM3-230213A), together with the five >1 PeV neutrinos detected by IceCube, could all originate from evaporating/exploding primordial black holes (PBHs). For ordinary Schwarzschild PBHs this interpretation conflicts with the differing KM3NeT/IceCube rates and gamma-ray constraints. The authors show that a population of PBHs carrying a new “dark U(1)” charge and spending most of their time in a quasi-extremal state suppresses 1 PeV emission relative to 100 PeV, making the observations and constraints consistent at 1σ — and such dark-charged PBHs could constitute all of the dark matter. If confirmed, such explosions could test Hawking radiation and illuminate the nature of dark matter.
A team including JSPS postdoctoral fellow Adrian Brines and Lecturer Shohei Aoki (University of Tokyo; also Associate Professor at Tohoku University) used data from several Mars orbiters to show that the enhancement of water vapour at high altitudes — long thought to occur mainly during southern-hemisphere summer — can also happen "out of season" during northern summer, revealing a new pathway by which martian water escapes to space. Mars is believed once to have held liquid water, and how that water was lost is a central puzzle: when water vapour is lifted to high altitudes it is broken up by solar ultraviolet light, and the light hydrogen atoms can then escape the planet's gravity. Analysing ESA ExoMars Trace Gas Orbiter data first, the team found high-altitude water vapour enhancement in northern summer, overturning the accepted picture. Cross-checking dust loading, atmospheric temperature and upper-atmosphere hydrogen abundance from multiple spacecraft showed the trigger was a "rocket dust storm" — an intense, localized and short-lived storm — that occurred on 21–22 August 2023 (Mars year 37). Published in Communications Earth & Environment.
Related keywords: Mars, 火星, water loss, 水の散逸, atmospheric escape, 大気散逸, rocket dust storm, ロケットダストストーム, dust storm, 砂嵐, water vapour, 水蒸気, hydrogen escape, 水素散逸, ExoMars, Trace Gas Orbiter, TGO, MMX, planetary atmosphere, 惑星大気, Communications Earth & Environment, 東京大学, 東北大学
💡 — A “cavity-array microscope” couples each atom to its own optical cavity — a path to million-qubit quantum computers / 原子1個ずつに専用の光共振器を結合する「共振器アレイ顕微鏡」を実現 ～100万量子ビット級量子コンピュータへの道～（スタンフォード大）
A Stanford University team led by Jonathan Simon (with co-first authors Adam L. Shaw, Anna Soper and Danial Shadmany) built a “cavity-array microscope”: a ~34-cm macroscopic optical resonator with intra-cavity microlens arrays that creates a two-dimensional array of more than 40 cavity modes, each strongly coupled to its own single atom in free space — a first. Previous experiments could only couple an entire atom array to one global cavity mode, fundamentally limiting addressability, parallelism and scalability. The new platform achieves above-unity peak cooperativity with micron-scale mode waists and spacings compatible with optical-tweezer arrays, enabling fast, parallel and non-destructive collection of single photons from every qubit at once. A larger prototype containing more than 500 cavities has also been demonstrated, pointing toward million-qubit quantum computers and large-scale quantum networks — with spin-offs in biosensing and even quantum-network telescopes for imaging distant planets. Published in Nature.
A team including Yuanhong Wang used a network of quantum sensors distributed across different cities to tighten constraints on axion dark matter. Axions — originally proposed to solve the strong CP problem — are among the best-motivated dark matter candidates, and axion fields can form topological defects such as domain walls during phase transitions in the early universe. As Earth crosses such a defect, the defect is expected to interact with nuclear spins and induce a transient signal. A single apparatus struggles to distinguish such rare, brief events from its own noise; by operating spin-based quantum sensors simultaneously at widely separated sites and keeping only signals correlated across stations, the team suppressed local false positives and improved limits on the coupling between axion-like particles and nuclear spins. Published in Nature.