Unveiling field-transverse spin anisotropy in the spin liquid candidate α-RuCl3 via spin Hall magnetoresistance Kitaev quantum spin liquids are highly sought-after states of matter that could lead to topologically protected, noise-resilient quantum computation. However, existing candidate materials are strong Mott insulators without charge carriers, making conventional electronic probing and manipulation challenging. Idzuchi et al. demonstrate that, by using heterostructures, interactions between α-RuCl3 and a neighboring noble metal with spin Hall effect can probe the directions of local moments. This reveals a characteristic spin anisotropy, providing an approach to study and control these exotic states.

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Optical characterization of proteins at single-molecule level Protein function emerges from stochastic transitions between complex conformational states. Conventional bulk measurements average over populations, obscuring molecular heterogeneity and rare but functionally important states. In this review, Yousefi et al. summarize a wide range of optical single-molecule approaches that overcome this limitation and enable direct observation of heterogeneity and transient protein states.

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Equilibrium spin polarization arising from chirality Chiral molecules have long been reported to generate spin polarization at equilibrium. This is an apparent contradiction to fundamental symmetry arguments. Theiler et al. show that the paradox stems from conflating equilibrium with microscopic time-reversal symmetry. Within a generalized symmetry framework, chiral systems with electronic correlations can host a cismagnetic phase: a zero-net-magnetization state with handedness-locked spin textures. This perspective reconciles diverse experiments and establishes chirality-driven spin selectivity as a thermodynamically consistent equilibrium phenomenon with implications for catalysis and quantum sensing.

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Correlation-tuned Fermi-arc topology in a Weyl ferromagnet Fermi arcs (FAs) are the hallmark surface states of Weyl semimetals. However, what determines their connectivity has remained rarely explored. Using Co3Sn2S2 as a model system, Peng et al. discover that correlation-driven band renormalization triggers topological transitions in FA connectivity, which is supported by calculations and scanning tunneling microscopy observations. This work establishes a connection between electronic correlation and topological features of FAs, providing a strategy for manipulating FAs to improve the electronic properties of correlated Weyl semimetals.

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Probability distribution for coherent transport of random waves Random-matrix theory predicts universal wave transport properties by averaging over random-media ensembles but cannot address wavefront-shaping experiments on a single fixed sample. Wang and Guo prove that the transmissivity distribution for random coherent waves through any fixed medium is universally a fundamental B-spline determined by the transmission eigenvalues. In the many-channel limit, this distribution converges to a Gaussian. The framework extends to other observables such as reflection and absorption, providing rigorous guidance for wavefront-shaping experiments.

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Suppression of phonon emission by Auger recombination-assisted carrier transfer in 1D/2D heterojunctions Bi1.3In0.7Se3 nanowires exhibit suboptimal performance in broadband photodetectors. Chen et al. reveal that 46.9% of their energy loss stems from coherent phonon oscillations at ∼1.29 GHz. Transferring carriers to WSe2 via Auger recombination significantly enhances visible light absorption intensity. The study verifies the interlayer electric field generated by this transfer process. Utilizing carrier-transfer technology not only eliminates coherent phonon oscillations but also boosts device detection efficiency nearly 10-fold.

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Universal bifurcation in glass relaxation dynamics revealed by ultra-low-frequency spectroscopy Understanding the ultra-slow relaxation dynamics of glassy materials is a fundamental challenge. Xing et al. introduce static square-wave mechanical spectroscopy to probe the microhertz regime with high precision, revealing a universal dynamical transition from VFT to apparent exponential temperature dependence in the deep glassy state and quantitatively verifying the intrinsic correlation between β- and α-relaxations, establishing a unified physical framework for glass kinetics.

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Deterministic ordering of polar skyrmions into a hexagonal crystal in ferroelectric ultrathin films via anisotropic strain Ferroelectric skyrmions can be created and manipulated with electric fields but often form disordered textures, limiting their functional applications. Ma et al. demonstrate that uniform anisotropic strain can reliably organize polar skyrmions into a stable hexagonal crystal by breaking in-plane symmetry. Remarkably, the resulting ordered state persists even after strain removal, indicating an intrinsic topological order. These findings provide a practical pathway for programmable, low-power control of ferroelectric skyrmion lattices.

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Optical propulsion and levitation of metajets Controlling optical forces across multiple directions remains a central challenge in light-driven manipulation and propulsion. Metasurfaces provide a powerful platform for tailoring photon momentum through engineered phase gradients. By unifying Newton’s rule of motion with generalized Snell’s law of optics, Kudtarkar et al. establish a theoretical framework and vector diagram to accurately describe force generation in metasurfaces for simultaneous in-plane propulsion and out-of-plane levitation, enabling light-driven motion control using both anomalous refraction and reflection in metasurfaces.

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Prospects and challenges for exchange bias in van der Waals heterostructures van der Waals (vdW) heterostructures offer atomically flat interfaces, enabling advanced spintronic functionalities. In this perspective, Kumar et al. explore how their layered nature affects exchange bias (EB), leading to self-induced EB without a separate antiferromagnetic layer, and how imperfections such as oxidation can enhance EB temperatures. It also discusses strategies to precisely control EB via electrical, electrochemical, and mechanical means, positioning vdW heterostructures as versatile platforms for probing interfacial magnetism and developing next-generation spintronic devices.

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Metasurfaces take flight with 3D optical propulsion and levitation Precise control over optical forces on objects with complex shapes represents a central challenge in nanophotonics. Kaushik Kudtarkar et al. demonstrate a new way to control microscopic objects by designing metasurfaces to refract light in unusual ways, showing the generation of optical forces that both push and lift tiny “metajets” in three dimensions, pointing toward scalable optical manipulation for applications from biology to space exploration.

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Navigation of a microswimmer in particle suspensions Microswimmer locomotion, especially in complex environments, can exhibit subtle and nontrivial physical features. Wu and Ishikawa compare pusher, puller, neutral, and force-driven microswimmers in particle suspensions, showing that pullers experience the lowest drag while pushers suffer the highest, where all microviscosity measurements remain below macroscopic values.

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Nonlinear hydrodynamic response of a quantum Hall system The quantum Hall effect is renowned for its precisely quantized Hall conductance, apparently suggesting an exactly linear current-voltage relation. Isobe uses hydrodynamic analysis to reveal that curved flows shaped by device geometry and a nonuniform electric field can induce nonlinearity via a centrifugal force acting on the incompressible quantum Hall fluid.

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The supersymmetric origin of chaos and its hidden topological order What is chaos? Despite much research on this ubiquitous and intriguing phenomenon, there is still no clear answer to this question. In this perspective, Ovchinnikov and Di Ventra discuss a radically new understanding of chaos as the spontaneous breakdown of a topological supersymmetry. This unusual yet rigorous point of view reveals that dynamical chaos is truly an ordered phase of dynamical systems, with far-reaching consequences in many branches of science.

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Heterogeneous dynamics in a polymer solution revealed through measurement of ultraslow convection Ultraslow dynamics are key to understanding relaxation and aging in soft-matter systems and yet can be challenging to measure. Chaney et al. use X-ray photon correlation spectroscopy to uncover ultraslow convection and hidden structural complexity in a polymer solution, showing that modest beam heating alters material dynamics without changing structure, highlighting an important consideration for interpreting X-ray measurements of time-dependent behavior.

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Tau as a matchmaker of the cytoskeleton The cytoskeleton emerges from interactions between actin filaments, microtubules, and associated proteins, but cellular complexity obscures the underlying mechanisms. Akter et al. show that co-reconstitution of actin and microtubules in giant vesicles reveals tau-driven crosstalk that depends on actin bundle stiffness and confinement, providing a minimal framework to dissect cytoskeletal organization.

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Extrinsic catch bonds may limit intrinsic ligand discrimination How T cells reliably distinguish between self and non-self ligands remains unresolved. Li and Wang show that catch-bond behavior can emerge from extrinsic geometric and mechanical constraints at membrane interfaces, independent of detailed molecular structure. Such constraints may challenge ligand discrimination based solely on intrinsic properties, potentially contributing to autoimmunity or immune evasion. By reconciling puzzling experimental observations, this framework motivates future efforts to probe systematic geometric and mechanical differences between agonist and non-agonist ligand-receptor complexes.

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Tau-driven coordination of microtubule-actin crosstalk in cell-sized vesicles Cells organize complex cytoskeletal networks to control shape and transport, but the physical principles underlying this coordination remain unclear. Using a minimal, cell-sized model system, Akter et al. show that the neuronal protein tau promotes cooperative assembly of microtubules and actin through confinement- and stiffness-dependent mechanisms. Experiments and simulations reveal that filament rigidity, crosslinking, and spatial confinement govern composite network formation, highlighting physical rules that shape cytoskeletal organization in cells.

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Electrically controlled propulsion of skyrmions in chiral nematic Design of soft matter capable of controllable microscale dynamics is a frontier of modern science. Jiahao Chen et al. demonstrate that an electric field can drive particle-like solitons-skyrmions in a chiral nematic along a preprogrammed trajectory with a variable speed within a two-dimensional plane. The effect is rooted in flexoelectric polarization of a deformed director field.

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Life-like processes in synthetic protocells under external fields Field actuation provides spatiotemporal control of synthetic protocells, yet “driven” responses range from passive manipulation to internally dissipative nonequilibrium dynamics. In this perspective, Willems et al. link protocell actuation to nonequilibrium statistical physics to clarify when field inputs produce life-like internal dynamics rather than simple manipulation. They propose a phenomenological classification across light, electric, and magnetic stimuli; survey examples of signaling, metabolism-like function, morphology, and transport; and highlight measurements to quantify time-reversal breaking at the protocell level.

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Dynamically resolved evolution and quantitative mapping of conformal skyrmion lattice Understanding how skyrmion crystals reorganize under driving is central to geometry-enabled spintronics. Zhao et al. show that skyrmion Hall-motion-driven lateral compression builds lattice curvature and triggers defect-mediated reorganization, producing a conformal skyrmion lattice with spatial gradients in skyrmion density and size while maintaining local angular order. Inverse conformal mapping quantitatively verifies conformality, and Lorentz transmission electron microscopy observes the conformal skyrmion ordering in Co9Zn9Mn2. Such geometry-controlled lattices offer a tunable source of stochastic bits for true random-number generation.

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Mixed-dimensional transport and evidence for one-dimensional edge modes in thin-film Bi4Br4 field-effect transistors The quasi-one-dimensional (quasi-1D) material Bi4Br4 is predicted to be a higher order topological insulator (TI), in which both the bulk and the surface states are gapped by 120 meV and 20 mV, respectively, and helical 1D modes at the edges are topologically protected. Zhang et al. reveal the contributions from 3D bulk, 2D surface, and 1D edge conduction channels via transport studies of Bi4Br4 thin films as a function of gate voltage, temperature, and magnetic field.

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Pressure-induced metal-insulator and paramagnet-altermagnet transitions in rutile OsO2 single crystals Rutile OsO2, isostructural to RuO2, has been theoretically predicted to host altermagnetism, yet experimental studies remain scarce. Zhao et al. report the successful growth of rutile OsO2 single crystals and show that OsO2 remains paramagnetic at ambient conditions while lying near the paramagnetic-altermagnetic phase boundary. High-pressure electrical transport measurements combined with hybrid functional calculations reveal that pressure enhances the Coulomb interaction U, driving altermagnetic phase evolution together with a metal-insulator transition.

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Hybridization of non-Hermitian topological interface modes One of the oldest topological edge states, the Jackiw-Rebbi (JR) interface mode, is resurging in photonics—now with a radiative, non-Hermitian twist. Wang et al. reveal the hybridization of two JR modes in subwavelength dielectric gratings. The hybridization leads to the formation of bonding/antibonding modes coupling with emitters exhibiting distinct characteristics, which can be tuned by adjusting the separation between the interfaces. This framework paves the way for advanced beam steering and light display applications while providing a foundation for exploring more intricate non-Hermitian physics.

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A universal design and benchmarking framework for indoor photovoltaics Indoor photovoltaics (IPVs) can sustainably power the growing smart-device ecosystem, yet they are commonly designed and evaluated using human-vision metrics and arbitrary spectra, impairing progress. Khampa et al. propose a universal, spectrum-aware framework for IPV design and benchmarking. By charting realistic indoor lighting diversity, they reveal an expanded optimal band-gap range (1.45–2.1 eV), introduce the spectral onset at 95% cumulative irradiance to unify IPV trends, and implement locus-based benchmarking to capture full efficiency spaces of IPVs, enabling fair cross-device comparisons.

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Computation-aided design of color centers for quantum information processing Color centers in semiconductors enable many quantum technologies, yet their properties remain difficult to predict. In this perspective, Li, Gali, and Huang focus on advances in computational methods and workflows for understanding and designing color centers, highlighting key theoretical challenges and emerging strategies toward more predictive, theory-driven discovery.

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Progress and prospects of magnetic topological materials for spintronic applications Magnetic topological materials are exotic compounds that merge robust topological electronic states with magnetic order. Recent developments include the quantum anomalous Hall effect, low-dissipation edge states, and spintronic applications. However, their low Curie and Néel temperatures limit stability at room temperature. In this review, Chen, Chi, and Moodera revisit the theoretical basis, classify various magnetic topological phases, and discuss their spintronic uses and ongoing challenges, offering a comprehensive overview of the field’s current status and future directions.

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Frozonium: Freezing anharmonicity in Floquet superconducting circuits Superconducting qubits typically have a fixed anharmonicity after fabrication, forcing a trade-off between highly anharmonic devices that are needed for qubit operations and highly harmonic devices that can be useful for quantum memory. Lewellen et al. propose a Floquet-engineered qubit, termed frozonium, that can dynamically access both regimes within a single device. In its harmonic regime, frozonium is robust against external dephasing, highlighting its promise as a platform for quantum memory.

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Flexoelectricity-enabled 360° polar locomotion of nematic skyrmions Liquid crystals offer a versatile platform to study solitons. Chen et al. demonstrate that skyrmions confined in a thin chiral nematic layer can be made electrically “directional” through flexoelectricity. By adjusting the voltage amplitude and polarity, their in-plane direction of motion can be steered continuously and their speed tuned. This turns a topological texture from a largely static pattern into a reprogrammable, field-driven quasiparticle and points to a general route for controllable transport of emergent structures in driven soft matter.

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Phosphonic-acid-reinforced polymer hole transport layers for deployable p-i-n perovskite photovoltaics In perovskite photovoltaics, the interfaces remain a crucial subject for improving performance. Degradation often proceeds from insufficient protection at interfaces. Kong et al. combine commonly used hole transport materials to create a modified hole transport layer that far outperforms the state-of-the-art single layers, improving performance and leading to a demonstration of a relatively long-term operational durability test for perovskite photovoltaics in low Earth orbit.

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