Physics

Solid-state semiconductor lasers underpin technologies from telecommunications and data storage to sensing, medical diagnostics, and emerging quantum communication. Polaritons, hybrid exciton-photon states, have further extended this reach by enabling room-temperature effects such as low-threshold lasing and strong optical nonlinearities. Organic semiconductors are attractive for polaritonics because of their large exciton binding energies, strong nonlinearities, and compatibility with solution processing. However, while solution-processed organic films have been widely explored, the optical cavities used for organic polariton lasing have typically relied on vacuum deposition, limiting truly scalable, low-cost, and accessible device fabrication. Here, we show that all-dielectric organic microcavities fabricated entirely by solution processing, including both the mirrors and active layer, operate in the strong coupling regime, exhibit polariton lasing, and support reversible, detuning-dependent redistribution of the condensate at high excitation densities, establishing an accessible and tunable platform for nonlinear organic polariton physics.

Developing highly efficient, stable, and wide-temperature NH3-SCR catalysts is one of the major challenges in industrial NOx emission control. Herein, we present an oxide-zeolite (OXZEO) hybrid design strategy for overcoming the challenge by spatially separating the NH3 storage and redox functions via isolated zeolitic Brønsted (B) acid sites, in contrast to conventional regulation strategies that rely on Lewis acid sites. Through a combination of in situ spectroscopy, in situ mass spectrometry, ab initio molecular dynamics, and density functional theory, we identify a previously unrecognized denitrification (deNOx) mechanism unique to the OXZEO system. Zeolitic B acid sites act as highly regulated NH3 storage, and the stored NH3 desorbs and migrates to oxide active sites as NH3 and NH4+, the latter effectively suppressing high-temperature NH3 over-oxidation. Using CeSnOx/Beta as the main model system for mechanistic investigation, we further demonstrate that this strategy can be generally extended to diverse zeolite topologies (BEA, CHA, MFI, FAU) and Ce-/Mn-based oxides, affording catalysts that achieve >80% NOx conversion and ~100% N2 selectivity over a temperature window exceeding 300 °C. This work highlights zeolite-mediated NH3 storage in deNOx, providing mechanistic insight into OXZEO structure-property relationships and guiding the development of next-generation NH3-SCR catalysts. Controlling nitrogen oxide emissions needs catalysts that work across harsh conditions. This study separates ammonia storage from reaction sites in oxide-zeolite hybrids, enabling stable, selective removal over a wide temperature range.

Non-Abelian braiding operations, a fundamental mechanism for implementing topological quantum gate operations, have recently been simulated using classical acoustic and photonic waves. However, such operations relied on adiabatic non-Abelian holonomies, which render the practical implementation intrinsically slow. Here, we theoretically propose and experimentally demonstrate a simulation of non-adiabatic non-Abelian braiding operations using quantum matter waves in a Bose-Einstein condensate. Within our framework, the effective braid strands are encoded by the momentum states, while the simulated braiding transformations arise from non-adiabatic non-Abelian holonomies. Experimentally, we verify the non-Abelian algebra by showing that different sequences of holonomic operations, applied to the same initial momentum state, yield distinct outcomes. Furthermore, we exhibit that these operations can be leveraged to prepare, transfer and distribute momentum quantum superposition states. Our work opens a fast non-adiabatic paradigm for non-Abelian geometric manipulation of both classical and quantum waves, and brings non-Abelian braiding operation into a regime applicable to quantum state manipulation. Non-Abelian braiding is a fundamental mechanism for implementing topological quantum computation. Here, the authors propose and demonstrate a quantum simulation of non-adiabatic non-Abelian braiding operation using a Bose Einstein condensate, realizing fast non-Abelian manipulation of matter waves.

The integration of light polarization into non-volatile memory enables angle-resolved information processing, unlocking new photonic channels for communication, computation and imaging. Yet practical polarization-sensitive memory remains rare. Here, we report a 2D rhenium disulfide (ReS2)/hafnium zirconium oxide (Hf0.5Zr0.5O2, HZO) ferroelectric field-effect transistor in which field-driven charge separation realizes polarization-resolved memory. The redistribution of photo-generated carriers at the heterostructure interface establishes an interfacial electrostatic field that modulates HZO ferroelectric domains and encodes non-volatile states. We also find that interfacial compressive stress induced by lattice mismatch shortens the Re-Re bond, which enhances the Re-Re chain anisotropy by 3.7x (from 2.67 to 9.98). Integrated into arrays for photonic neural networks, the device attains >93% accuracy on a transformer model. Leveraging the cumulative switching property of HZO with sequential optical signals, the device enables in-situ multiplication and accumulation of inputs over time, achieving 4x area saving with <1% accuracy loss. Beyond amplitude and phase, the demonstrated electro-optic device enables optical polarization as an additional information read-out, which significantly increases the information density of photonic-based computing. Light polarization-sensitive optoelectronic memory devices would be useful for various photonic applications, but they are difficult to implement. Here, the authors report 2D ReS2/hafnium zirconium oxide (HZO) electro-optic memory devices, enabled by polarization-dependent photocarrier accumulation at the interface modulating the HZO ferroelectric domains.

Sustainable thermal management of high-heat-flux electronics beyond Moore’s Law requires micro thermoelectric coolers (μ-TECs) that are both high-performance and environmentally sustainable. However, state-of-the-art μ-TECs rely on Bi2Te3-based materials, whose tellurium scarcity, toxicity concerns and limited mechanical robustness hinder widespread adoption. Mg-based thermoelectric materials offer a promising alternative but remain challenging to integrate into microscale devices. Here we show that a low-temperature, water-free fabrication strategy enables tellurium-minimized μ-TECs based on n-type Mg3(Bi,Sb)2 and p-type MgAgSb. Using magnetron sputtering as a cold bonding approach, we fabricate compact 12-pair microdevices (2.95 × 4.35 × 1.4 mm3), with thermoelectric legs approximately 3% the size of previously reported Mg-based devices. The resulting μ-TECs achieve a power density of 4.34 W cm−2 and a packing density of 93.5 pairs cm−2. Our work establishes a scalable route for sustainable thermoelectric cooling and a viable alternative to conventional Bi2Te3 technologies. This study reports Mg-based micro thermoelectric coolers fabricated via a low-temperature process, achieving high cooling performance and enabling a scalable, sustainable alternative to conventional Bi2Te3-based devices for thermal management.

The nuclearity of active sites in heterogeneous Ziegler-Natta catalysts fundamentally governs polyolefin microstructure, yet its dynamic regulation during polymerization remains challenging. Here, we report a liquid containing polymerization strategy that directs the formation of dinuclear titanium species through periodic wetting-drying of inert n-hexane on the catalytic particles. Operando spectroscopy reveals how this unique fluid environment promotes the formation of dinuclear centers, in contrast to the monomeric species dominant in conventional gas- or slurry-phase systems. These dinuclear sites substantially enhance comonomer incorporation efficiency, yielding polyethylene with more uniform short-chain branching (SCB) distribution. Diffusion-ordered NMR spectroscopy further confirms that the capillary condensation of inert n-hexane in catalyst pores during liquid containing polymerization can enrich 1‑octene concentration by over twofold compared to the bulk slurry environment, thereby effectively promoting the SCB content in the synthesized polyethylene. This work establishes reactor fluid dynamics as a powerful tool for in-situ active-site engineering, opening avenues for selective control of polymer microstructure without modifying catalyst composition. The nuclearity of active sites in heterogeneous Ziegler–Natta catalysts plays a key role in determining polyolefin microstructure yet remains difficult to control during polymerization. Here, the authors use a liquid-containing polymerization strategy to induce dinuclear titanium species via periodic wetting–drying of n-hexane, enabling polymer microstructure control without altering catalyst composition.

Machine-learning interatomic potentials have demonstrated power-law scaling in predictive accuracy as training data and model capacity increase, but it remains unclear whether models trained at scale acquire interpretable chemical concepts. Here we show that an E(3)-equivariant machine-learning interatomic potential learns local bond information without direct supervision of bond properties. To expose this information, we develop an edge-wise emergent energy-decomposition framework and apply it to an Allegro neural-network potential trained on SPICE2, a dataset composed of stable molecular structures. The framework analyzes edge-wise energy contributions obtained from the trained model and their distributions together with information entropy to examine how data size, data composition and model-training scenarios shape the internal representation of chemical bonds. The resulting bond-dissociation energy estimates for archetypal bond types agree quantitatively with literature values and are consistent across models trained on organic and inorganic datasets. We further examine a hybrid training set and find that combining complementary chemical data improves transition-state energy-prediction accuracy while reshaping the learned bond representations. These results indicate that scalable interatomic potentials can acquire transferable bond concepts without explicit bond-energy labels, providing a way to analyze the transition-state energy-prediction problem.

The macromolecular architecture of plant secondary cell walls governs wood’s mechanical and biochemical properties, yet its natural intra-species variability remains poorly characterized. Here, we combined ¹³C solid-state NMR (ssNMR), multivariate statistical analysis, and molecular modeling to profile nanoscale structure across 13 genetically diverse Populus trichocarpa genotypes grown in ¹³C-enriched atmospheres. SsNMR-derived phenotypes spanning composition, structure, mobility, and inter-polymer proximities reveal a conserved architecture, with a subtle yet coordinated variation organizing into dominant structural and secondary mobility axes. A representative atomistic model captures these features and reproduces experimental metrics. Molecular dynamics simulations support a weak but consistent positive correlation between cellulose abundance and crystalline-like order, with interior cellulose chains enriched in tg (trans–gauche) conformations without expanding crystalline cores. Together, experiment and simulation reveal a genetically buffered, broadly conserved nanoscale architecture across genotypes, where subtle fine-tuning of cellulose bundling and matrix packing balances mechanical performance with biological function. Plant secondary cell wall architecture determines wood’s biomechanical properties. Here via NMR and atomistic modelling, the authors show that secondary cell wall nanoscale architecture is broadly conserved in 13 genetically diverse poplar trees but fine-tuned through subtle changes in cellulose bundling.

Achieving the superior tensile strength of individual carbon nanotubes (CNTs) in macroscopic fibers depends on how CNTs are assembled. This study reports a fluidics approach: spraying high-velocity ethanol to scour and shrink pre-made CNT fibers. Experimental measurements show that the continuous scouring and shrinking induce significant improvements of the CNT alignment and packing density, leading to large increases of the van der Waals forces between CNTs and thus the tensile strength of the fibers. Under optimal conditions, the new CNT fibers achieve a specific tensile strength of 7.5×106 N⋅m⋅kg⁻1 (or 7.5 N⋅tex⁻1) and absolute strength of 12.5 GPa, approaching the lower limit of individual CNTs. They also exhibit a high Young’s modulus of 370 GPa, electrical conductivity of ~3×106 S⋅m⁻1, and thermal conductivity of ~968 W⋅m⁻1⋅K⁻1. This fluidics approach offers a promising route to develop high-performance CNT materials comparable to CNT individuals. Scouring and shrinking using fast flow of ethanol induced large improvements of carbon nanotube alignment and packing density and thus the tensile strength of the fiber to 12.5 GPa.

Nowotny chimney ladder crystals combine features of ordered crystals and amorphous solids, making them attractive thermoelectric materials because of their intrinsically low thermal conductivity. We investigate the intermetallic compound Ru2Sn3 and show that, despite its crystalline order, its heat capacity exhibits a boson-peak-like glassy anomaly at 8-14 K. Combining experiments with first-principles calculations and molecular dynamics simulations, we trace this behavior to low-energy optical phonons emerging from the chimney ladder structure. These modes strongly couple to acoustic phonons, producing hybridization and avoided crossings that reshape the vibrational spectrum and cause the hybridized acoustic branches to contribute directly to the anomaly. Thermoelectric measurements reveal additional glass-like signatures linked to these excitations, while the electrical resistivity displays an extended linear temperature dependence and an anomalously large quadratic contribution at low temperatures. A simple theoretical model based on electron scattering by overdamped phonons qualitatively accounts for these observations. The authors show that the hybridization of low-energy optical and acoustic phonons in the chimney ladder crystal Ru2Sn3 gives rise to glass-like thermodynamic and transport anomalies and anomalous thermoelectric behavior.

Two-dimensional (2D) spin valves are important for energy-efficient memory and computation devices but remain limited in achieving high magnetoresistance (MR) ratios at room temperature due to the lack of suitable ferromagnetic materials, optimal spin transport channel spacers, and great challenges in atom-level interface control in heterostructures. Here we report a record room temperature MR up to 103% for all-van der Waals (vdW) heterostructures by employing vdW ferromagnetic Fe3GaTe2 (FGaT) electrodes with vdW monoelemental black or violet phosphorus spacers. Notably, these devices exhibit magnetic field angle-independent MR while retaining anisotropic coercivity. This behavior originates from domain wall motion-driven magnetization reversal and the strong perpendicular magnetic anisotropy of the FGaT. First‑principles transport calculations reveal an intrinsic zero‑bias MR of up to 330% at the Fermi level for ideal interfaces and a monolayer spacer, supporting the high spin‑polarized transport capability of these heterostructures. The experimental room temperature MR is lower due to finite bias, temperature, spacer thickness, and realistic interface conditions. These results demonstrate the potential of 2D vdW monoelemental phosphorus as a high-efficiency spin-transport channel in room temperature all-vdW spin valves and provide a framework for designing field-orientation-resilient non-volatile spintronic memory devices. The authors found that a room temperature magnetoresistance of 103% is achieved in all-van-der-Waals spin valves using Fe3GaTe2 and black phosphorus, and that the MR ratio is independent of field direction due to domain-wall-motion-driven magnetization switching dynamics in Fe3GaTe2.

Dissipative sensors typically use linear resonators with impedance matching to achieve maximal signal and fast operation. The impedance matching, however, sets an upper limit to the bandwidth of the readout. In this paper, we present a nonlinear resonator performing the readout of a double quantum dot charge state via a charge-sensing quantum dot. We show that by driving the resonator in the nonlinear regime, we achieve a near-unity signal for a dissipative sensor. This despite not satisfying the sensor impedance matching requirements necessary for such large signals in the linear regime. Our experiments, supported by numerical calculations, demonstrate that the signal increase stems from the sensor dissipation shifting the onset of the nonlinear resonator response. By lifting the matching requirement, we open up an avenue to ultra-fast charge detectors as the resonator input-output coupling - setting the detector bandwidth - does not have to match to the typically much slower sensor dissipation rate.

Recent predictions of orders of magnitude larger orbital current effects compared with spin currents have attracted considerable interest. However, orbital currents must first be converted into spin currents to interact with the static magnetization dominated by spin angular momentum in conventional magnets. By using a magnet dominated by orbital angular momentum (OAM), we demonstrate a 70-fold enhancement in orbital Hall magnetoresistance in cobalt II oxide/copper (CoO/Cu*), compared with spin Hall magnetoresistance in cobalt II oxide/platinum (CoO/Pt). This arises from interactions between dynamic OAM from surface-oxidized Cu* and static OAM in the antiferromagnetic insulator CoO. Our results show how by using OAM-dominated materials, we can harness the benefits of giant orbital currents that have not been possible using conventional spin-dominated magnets.

N ferroelectrics exhibit exceptional polarization and thermal stability, making them highly promising for a wide range of electronic applications. However, a more profound understanding is required regarding the atomic-scale mechanism through which cation substitution lowers the switching energy barrier and thus reduces the coercive field. We used spherical aberration-corrected transmission electron microscopy to reveal a periodic modulation of cation-anion spacing along the polarization direction, forming alternating atomic dipole layers. This modulation arises from energetically favorable chemical ordering of aluminum and scandium atoms between adjacent layers, with layer-resolved asymmetry in atomic arrangement. In situ imaging directly captures atomic-scale, noncollective, stepwise polarization switching, revealing intermediate states and local spacing fluctuations. Compositional inhomogeneity in these dipole layers creates multiple transient states that reduce the switching energy barrier. Our findings connect atomic-scale dipole structures to polarization switching kinetics, enabling the rational design of wurtzite ferroelectrics.

Disorder-induced phenomena in quantum many-body systems pose a challenge for analytical and numerical approaches at relevant time and system scales. To reduce the cost of disorder sampling, we investigated quantum circuits initialized in states that form tunable superpositions over all disorder configurations, which in lattice gauge theories can be interpreted as superpositions over gauge sectors. On the experimentally accessible timescales, we observed localization in the absence of disorder in one and two dimensions: Perturbations failed to diffuse despite fully disorder-free evolution and initial states. However, entropy measurements revealed that superposition-prepared states fundamentally differ from those obtained by direct disorder sampling. Leveraging superposition, we propose an algorithm with a polynomial speedup in sampling disorder configurations, a long-standing challenge in many-body localization studies.

A particle detected at the South Pole was born in a galaxy that churned out stars when the Universe was young. A particle detected at the South Pole was born in a galaxy that churned out stars when the Universe was young.

In homo- or hetero-interface of two dimensional materials, beyond the rigid moiré patterns, the marginal twisting ensures local commensurate stacking registry via reconstruction and thus introduces versatile structural subtleties into the many-body interplay, enabling the coexistence and tessellation of multiple domain-specific emergent states. In this work, we demonstrate that monolayer 1T-TiSe2 epitaxially grown on 2H-NbSe2 undergoes spontaneous moiré reconstruction, therein developing distinct charge density wave configurations dictated by stacking orientation. In parallel-stacked regions, the native 2×2 charge order of TiSe2 persists but experiences domain-selective modulation. Antiparallel-stacked systems host distinctive $$\sqrt{3}\times \sqrt{3}$$ and 2×1 charge orders which exhibit intertwined phenomena unveiled by scanning tunneling microscopy—including bias-toggled negative differential conductance, competitive inter-order penetration, and defect-mediated local ordering reconstitution. These observations coalesce into a unified paradigm, where the $$\sqrt{3}\times \sqrt{3}$$ charge order is quantum confined and isolated in single domain, while the 2×1 charge order permeates across domains, forming a percolative network. Our results demonstrate that the marginal-twist moiré reconstruction is a designer platform to generate rich emergent charge density wave landscapes, which also serves as a nanoscale testbed to decipher their disparate microscopic nature. Hetero-interfaces can exhibit domain-specific emergent states. Here, the authors demonstrate that monolayer 1T-TiSe2 on 2H-NbSe2 exhibits $$\sqrt{3}\times \sqrt{3}$$ charge order which is quantum confined in defect-free domains while 2 × 1 charge order permeates across domains, forming a percolative network.

Conductive two-dimensional covalent organic frameworks (2D COFs) possess intrinsic π–conjugation and long-range order, yet their electrical performance in thin-film devices remains constrained by grain boundaries and amorphous regions that interrupt charge transport. Here we report a simple and scalable strategy to overcome these limitations by bridging polycrystalline COF domains with molecularly dispersed conjugated polymers (CPs). Guided by electronic alignment, geometric compatibility, and chain-length criteria, we identify COF–CP combinations that exhibit markedly enhanced conductivity when assembled into heterostructures. By demonstrating that electrical property enhancement occurs only below the CP crystallization threshold, we show that bridging CPs require short-range ordered or near-amorphous configurations to effectively span COF grains and establish continuous transport pathways. This approach is compatible with wafer-scale fabrication and enables ppb-level NO2 sensing by coupling COF porosity with CP-mediated charge transport. Our results establish a rational polymer-bridging strategy for COF-based electronic materials and identify key design parameters for its extension to other COF–CP systems. The electrical performance in COF thin-film devices remains constrained by grain boundaries and amorphous regions that interrupt charge transport. Here the authors report a simple and scalable strategy to overcome these limitations by bridging polycrystalline COF domains with molecularly dispersed conjugated polymers.

Abstract Achieving near-theoretical strength and elastic limits in crystalline solids remains challenging, yet defect sensitivity typically restricts such behavior to nanometer scale specimens. Here we report experimental evidence of near-theoretical strength and large elastic tensile strains in micrometer scale TiB 2 ceramics, produced in situ by eutectic solidification in steel. In situ bending of crystallographically oriented cantilevers, fixed end beams and C-shaped structures, combined with specimen specific finite element analysis, reveals tensile side stresses of tens of gigapascals and elastic strains up to 9%. Direct microscale tension shows that a large gauge volume exceeding 4 μm 3 sustains nearly uniform tensile stress of ~13 GPa without fracture before grip edge failure, providing a conservative lower bound tensile benchmark, while micropillar compression confirms high stress bearing capability. These results establish eutectic solidification as a scalable pathway to suppress strength limiting defects over micrometer scale volumes, extending near-theoretical ceramic strength beyond the nanoscale and enabling robust microarchitected components.

In the version of this article initially published, there were inaccuracies in the Methods, Fig. 1 and Supplementary Information regarding the synthesis of covalent organic frameworks (COFs). In the sixth paragraph of the Methods “Rotating ring-disk electrode (RRDE) measurement” section, the text now reading “After refinement, the final R wp and R p values were achieved: 3.98% and 5.86% for ATP-COF-1, and 3.81% and 4.767% for ATP-COF-2” replaces the original “After refinement, the final R wp and R p values were achieved: 4.34% and 7.74% for ATP-COF-1, and 3.78% and 5.78% for ATP-COF-2.”

Nanodiamonds can host atom-sized light emitters for quantum sensing and imaging, but making nanodiamonds that are small, crystalline and uniform has been difficult. A single-step process for making nanodiamonds only 3–4 nanometres in size uses planar carbon ‘nanographene’ molecules with hydrogen atoms on the edges, and can be adapted to generate fluorescent nanodiamonds. Molecular nanodiamonds with a narrow size distribution of 3 to 4 nanometres can be made on the milligram scale.

Transistors based on two-dimensional (2D) materials are on the roadmap for the beyond 1 nm logic technology node1. This stems from their ultrathin thickness and defect-free surfaces, granting remarkable electrostatic gate control2–5. The physical channel length of 2D transistors may eventually reach <10 nm for advanced node devices. However, the equally important scaling limit for metal contacts remains unknown because of the lack of technology to directly probe the carrier injection region in contact areas. Here we use cross-sectional scanning tunnelling microscopy to directly measure the carrier transfer length as approximately 2.0 nm at the contact region of a bismuth-contacted monolayer MoS2 transistor. This approach allows contact scaling constraints to be determined, providing information for the development of future ultra-scaled electronic devices. Cross-sectional scanning tunnelling microscopy shows a 2 nm carrier transfer length in bismuth-contacted monolayer MoS2 transistors, defining metal-contact scaling limits for sub-10 nm 2D electronic devices.

Abstract Most stars, including our Sun, will one day evolve into red giants and, subsequently, white dwarfs. Several planet candidates have recently been identified orbiting white dwarfs 1–4 , demonstrating that planets can survive the stellar post-main-sequence stage intact. Little is known about the atmospheric composition of post-main-sequence planets, with the most evolved transiting planets with atmospheric detections so far orbiting subgiants 5,6 . Here we report an atmospheric detection for the white dwarf planet WD 1856 b, achieved through transmission spectroscopy with the James Webb Space Telescope (JWST) Near-Infrared Spectrograph (NIRSpec) PRISM. Our 0.5–5.0-μm spectrum reveals the presence of hydrocarbons (odds ratio of 167:1–5,377:1, with CH 4 preferred at 17:1–30:1), aerosols (2 × 10 5 :1–2 × 10 6 :1) and thermal emission from the planetary nightside (2 × 10 63 :1–2 × 10 73 :1). Our spectral analysis constrains the mass of WD 1856 b to 4.3–10.9 M J , finds a carbon-enriched atmosphere (with a CH 4 abundance of approximately 7%) and an effective temperature exceeding the expected planetary equilibrium temperature (390–412 K versus 160 K). On the basis of cooling models, these results indicate that WD 1856 b underwent a migration-related reheating event 3.0–5.5 Gyr into the white dwarf phase, consistent with post-main-sequence tidal evolution to the present-day 0.02- au circular orbit. Our results provide a window into the ultimate fate of giant planets orbiting stars with masses similar to our Sun.