We report on a blinded search for dark matter (DM) using ionization-only (S2-only) signals in XENONnT with a total exposure of $7.83\text{Tonne-year}$ over 579 days in three science runs. Dedicated background suppression techniques and the first complete S2-only background model in XENONnT provide sensitivity to nuclear recoils of $[0.5,5.0]{\mathrm{keV}}_{\mathrm{nr}}$ and electronic recoils of $[0.04,0.7]{\mathrm{keV}}_{\mathrm{ee}}$. No significant excess over the expected background is observed, and we set 90% confidence level upper limits on spin-independent DM-nucleon and spin-dependent DM-neutron scattering for DM masses between 3 and $8\mathrm{GeV}/c^2$, as well as on DM-electron scattering, axionlike particles, and dark photons, improving on previous constraints. For spin-independent DM-nucleon scattering, we exclude cross sections above $6.0\times {10}^{-45}{\mathrm{cm}}^2$ at a DM mass of $5\mathrm{GeV}/c^2$, pushing the XENONnT sensitivity closer to the region where coherent elastic neutrino-nucleus scattering becomes an irreducible background.

We demonstrate a turbulence mechanism that reconciles high plasma confinement with efficient heat exhaust—a central challenge for fusion energy. Global two-fluid turbulence simulations of the reactor-relevant quasicontinuous exhaust regime on the ASDEX Upgrade tokamak reveal that a quasicoherent mode drives mesoscopic oscillations of the pedestal boundary across the magnetic separatrix and ejects ballistic filaments (blobs), reproducing both the mean profiles and turbulent fluctuations observed experimentally. This behavior arises from a synergistic interplay between kinetic ballooning modes and resistive X-point modes straddling the separatrix. These first-principles results place extrapolations to future fusion reactors on a firm physical footing.

The quantum theory of the electromagnetic field enables the description of multiphoton states exhibiting nonclassical statistical properties, often reflected in non-Gaussian phase-space distributions. While non-Gaussianity alone does not fully characterize quantum states, several classifications have been proposed to hierarchize non-Gaussian states according to physically or informationally relevant resources. Here, we provide a physical interpretation of non-Gaussianity and connect it to a computational perspective by showing how a prominent classification—the stellar rank—emerges as a limiting case of the roots of polynomials that univocally represent bosonic states defined with a quantized phase reference, namely the Majorana polynomials. A direct consequence of our results is a revised interpretation of both the stellar rank and non-Gaussianity itself: when superselection rules are properly taken into account, quadrature non-Gaussianity—and nonzero stellar rank—act as witnesses of particle entanglement, rather than being linked with photon addition to Gaussian states as previously assumed. In addition, we show that, because the stellar rank depends on a specific choice of coherent states, its relation to computational resources and potential quantum advantage is inherently basis dependent, being naturally tied to quadrature eigenstates as the computational basis. Motivated by this observation, we generalize the notion of stellar rank to arbitrary computational bases, thereby establishing it as a genuine witness of bosonic resources that may enable quantum advantage.

We report a Si-CMOS-compatible photodiode for room temperature short-wavelength infrared detection. The architecture integrates Te-hyperdoped silicon with light-trapping structures to achieve a breakthrough in sub-band-gap efficiency. Specifically, by combining surface texturing and a back reflector, we boost absorptance to $\approx 85\%$, enabling the observation of transport dynamics at room temperature that were previously obscured in planar devices. We report a peak external quantum efficiency of 2.3% at $1.27\mathrm{\mu }\mathrm{m}$, exceeding commercial Si-PIN performance by 3 orders of magnitude. The physical origin of this enhancement is attributed to bias-assisted tunneling between the Te impurity band and the Si valence band, evidenced by a distinct spectral shoulder at 0.4–0.6 eV. Our results, supported by a specific detectivity of $4\times {10}^{10}{\mathrm{cmHz}}^{1/2}{\mathrm{W}}^{-1}$ and $32\mathrm{\mu }\mathrm{s}$ response times, establish hyperdoped silicon as a viable platform for high-performance, room temperature SWIR photonics.

Ensembles of atoms interacting via their Rydberg levels, known as “superatoms” for their ability to encode qubits and to emit single photons, attract increasing attention as building blocks for quantum network nodes. Assessing their performance requires an accurate, physically informative, and numerically scalable description of interactions in a large and disordered ensemble. We derive such a description from first principles and successfully test it against brute-force numerics and experimental data. This model proves essential to make quantitative predictions about gate fidelities or photon emission efficiencies and to guide experiments toward large-scale superatom-based systems.

The quantum Hall effect and topological insulators have sparked significant interest in the investigation of topological photonics, mechanics, and acoustics with the objective of realizing robust topological one-way states. However, diffusion, such as heat transport, neither responds to magnetic fields nor possesses intrinsic spin, and is therefore devoid of propagation characteristics typical of wave dynamic fields. Accordingly, the identification of Chern or topological insulators within a diffusive context has long been considered challenging, if not impossible. Here, we propose a thermal analog of the Haldane model that supports one-way transport of heat. We endow the temperature field with a degree of freedom corresponding to the wave function’s phase, and demonstrate that complex couplings can be effectively synthesized by tailoring intralayer and interlayer hopping. Furthermore, we have fabricated the thermal Haldane lattice by incorporating actively controlled, programmable thermal sources, and experimentally observed the evidence of thermal chiral edge states. This Letter may offer insights into the flexible and robust manipulation of heat and mass transfer.

Topological insulators, including the first-order and higher-order topological insulators, drive transformative advances in condensed-matter physics and material sciences. Although nonzero first-order topological indices (e.g., Chern and spin-Chern numbers) fundamentally render the conventional higher-order topological indices ill-defined, first-order topological systems can still support higher-order topological corner states as Jackiw-Rebbi-type modes from edge band topologies. Here, by contrast, we experimentally implement a distinct relative-polarization mechanism and realize higher-order topological corner states embedded in first-order topological bands using an acoustic spin-Chern insulator. The higher-order topology in our system originates from the quantized differences in spin-resolved bulk polarizations at domain walls, notwithstanding the ill definition of the polarizations themselves in the crystal bulk due to the nonzero spin-Chern numbers. As a result, topological corner states emerge, coexisting with helical edge states within the same bulk band gap. Our Letter evidences a polarization-difference-induced higher-order topology embedded in first-order topological bands and may facilitate the development of topological devices in acoustics.

Altermagnets break a combination of time-reversal and rotational symmetries without generating a net magnetization. As such, the order parameter of $d$-wave altermagnets has the same symmetry as magnetic multipoles and couples to the product of a magnetic field and uniaxial strain. We combine elastocaloric experiments, free-energy modeling, and first-principles calculations on ${\mathrm{MnF}}_2$ to establish a thermodynamic probe of the predicted finite-temperature altermagnetic critical point. These results pave the way to explore altermagnetic quantum criticality in $d$-wave materials and beyond.

The synthetic frequency dimension, which realizes fictitious spatial dimensions from the spectral degree of freedom, has emerged as a promising platform for engineering artificial gauge fields in studying quantum simulations and topological physics with photons. A current central task for frequency-domain photons is the creation and manipulation of nontrivial non-Abelian field strength tensors and to observe their governing dynamics. Here, we experimentally demonstrate a minimal scheme for creating non-Abelian electric fields in a photonic frequency chain using a polarization-multiplexed, time-modulated ring resonator. By engineering spin-orbit coupling via modulation phase offset, polarization rotation, and polarization retardation, we achieve programmable control over synthetic Floquet bands and their quasimomentum spin-resolved textures. Leveraging self-heterodyne coherent detection, we demonstrate Zitterbewegung—a trembling motion of photons—induced by non-Abelian electric fields on the frequency chain. We further observe the interference between Zitterbewegung and Bloch oscillations arising from the coexistence of non-Abelian and Abelian electric fields. Our Letter bridges synthetic dimensions with non-Abelian gauge theory for versatile photonic emulation of relativistic quantum mechanics and spinor dynamics and can be instrumental in applications like frequency-domain optical computation and multimodal frequency comb control.

In this Letter, we consider constraints on the low-energy spectrum of scalar amplitudes with higher-spin exchanges. Assuming unitarity, crossing symmetry, and superconvergent high energy behavior, we demonstrate that the spectrum that maximizes the leading higher spin couplings of the second and third resonances is consistently given by a linear trajectory. We work strictly in ten dimensions although we expect analysis in other dimensions to be similar. For gravitational theories, the optimal spectrum is the linear trajectory defined by the mass and spin of the graviton and the lightest spin-4 resonance.

The Nernst effect in superconductors is typically linked to fluctuating Cooper pairs above $T_c$ or vortex motion below $T_c$. We show instead that Berry curvature of Bogoliubov quasiparticles can generate an intrinsic Nernst response in a clean, vortex-free superconducting state. Focusing on two-dimensional systems with Ising spin-orbit coupling, relevant to transition-metal dichalcogenides, we identify two regimes: an intervalley $s$-wave paired state where a weak magnetic field activates the effect, and an intravalley chiral $p$-wave paired state that exhibits a spontaneous charge or spin Nernst response without a field. We propose an experimental setup that circumvents screening and provide estimates of the signal magnitude. Our results establish the Nernst effect as a direct probe of Berry curvature and pairing symmetry in two-dimensional spin-orbit-coupled superconductors.

The interaction of light with correlated quantum matter in two-dimensional (2D) materials offers a powerful platform for exploring emergent quantum phenomena. Here, we report the realization of Landau polaritons in a monolayer tungsten diselenide (${\mathrm{WSe}}_2$) integrated into an optical microcavity. By embedding a two-dimensional electron gas (2DEG) in the monolayer and applying a perpendicular magnetic field, we achieve strong coupling between cavity photons and interband Landau level (LL) transitions, giving rise to hybrid light-matter quasiparticles. These Landau polaritons exhibit valley-dependent oscillations in the coupling strengths and resonance energies, driven by the electrical and magnetic filling of valley-contrasting Landau levels. Moreover, intervalley correlations between LL transitions and opposite-valley electrons lead to nonlinear renormalization of both LL transition energies and Landau-polariton coupling strengths. Our results establish a new paradigm for cavity quantum electrodynamics in correlated 2D systems and demonstrate control of Landau polaritons via the valley degree of freedom, opening new avenues for light-mediated manipulation of quantum phases.

Atomic force microscopy (AFM) with a functionalized tip can resolve the chemical structure of single molecules, but its application has been limited by slow imaging speeds and the restriction to constant-height operation. Here, we overcome these limitations by operating a Si cantilever in its second resonance mode, achieving exceptional force sensitivity. This enables robust, constant-height chemical-structure imaging at speeds up to 200 nm/s—over 60 times faster than previously reported. The enhanced sensitivity also resolves molecular bonds directly in constant-frequency-shift topographic images, a mode crucial for studying nonplanar systems. Our approach significantly expands the capabilities of AFM, opening new avenues for investigating the structure of three-dimensional molecules and tracking the dynamics of on-surface chemical reactions.

We implement a quantum neural network on trapped-ion and IBM superconducting quantum computers for Modified National Institute of Standards image classification. Feedforward is realized through qubit rotations conditioned on measurement outcomes from previous layers. The network is trained classically, while inference is performed experimentally on quantum hardware. A tunable interpolation parameter connects the classical and quantum regimes. Moderate values improve classification performance by introducing measurement uncertainty. For borderline images misclassified classically but correctly identified quantum mechanically, we observe strong deviations from idealized simulations due to physical noise, consistent with fluctuations between nearby minima in the classification landscape. We further benchmark noise by inserting additional single- and two-qubit gate pairs into the circuits. Our results motivate more complex quantum neural networks on noisy intermediate-scale quantum devices and suggest a possible route toward classically nonsimulable architectures.

Understanding dissipation in topological insulators is key to both fundamental physics and applications in spintronics, quantum computing, and low-power devices. Contrary to conventional expectations, dissipation in topological insulators need not rely on backscattering or dephasing: we show that finite-frequency local shot noise couples to the electromagnetic environment and generates near-field radiation, creating a nonlocal loss channel even at quantized conductance with vanishing global shot noise. Using a nonequilibrium Green’s-function framework, we link the local noise tensor to the spectral Poynting vector and compute persistent local noise in realistic two- and three-probe quantum Hall/quantum anomalous Hall interfaces where inequivalent edge modes overlap. This produces near-field “hot spots” measurable by scanning microscopy. We also give a design criterion: enforce spin-sector orthogonality to eliminate edge-mode overlap, thereby suppressing this loss channel. Our results provide a microscopic mechanism for hidden dissipation and a practical blueprint for diagnosing and reducing energy loss in topological electronics.

Inspired by the recent experimental discovery of superconductivity emerging from a time-reversal symmetry-breaking normal state in tetralayer rhombohedral graphene, we here investigate superconducting instabilities in this system. We classify the possible pairing instabilities, including states with commensurate and incommensurate center of mass momenta. As rotational symmetry is broken in the latter type of pairing states, their momentum-space structure is most naturally characterized by a “valley-independent Chern number,” measuring the relative chirality between the normal and superconducting state. We further demonstrate that superconductivity can condense at multiple incommensurate momenta simultaneously, leading to the spontaneous formation of a translational-symmetry-breaking superlattice superconductor. Studying multiple different pairing mechanisms and varying the degree of spin and valley polarization in the normal state, we compare the energetics of these superconductors. Our results demonstrate that valley-imbalanced rhombohedral tetralayer graphene can give rise to rich superconducting phenomenologies.

The Sachdev-Ye-Kitaev (SYK) model has attracted widespread attention due to its relevance to diverse areas of physics, such as high temperature superconductivity, black holes, and quantum chaos. The model is, however, extremely challenging to realize experimentally. In this Letter, we show how a particular form of Floquet engineering, termed “kinetic driving,” effectively eliminates single-particle processes and creates quasirandom all-to-all interactions when applied to models of Hubbard type. For the specific case of the Bose-Hubbard model, we explicitly verify that the driven system indeed reproduces SYK physics by direct comparison of the spectral form factor and out-of-time ordered correlation functions. Our findings indicate that a cold-atom realization of kinetic driving—achieved through modulation of hopping amplitudes in an optical lattice—offers a practical and accurate platform for quantum simulation of the SYK model.

The excess entropy scaling law is an empirical yet powerful structure-dynamics relationship for liquids and glasses. Here, we report the first experimental study that extends this entropy scaling concept to spin lattices, a fundamentally different class of disordered matter. We employ an in situ controlled buckled colloidal monolayer, which serves as a classical two-dimensional Ising lattice. Across isotropic compression, shear, and attraction-tuning experiments, the data reveal an exponential relationship, ${\tau }_{\alpha }\propto \exp (c{S}_{\mathrm{em}})$, between the spin relaxation time ${\tau }_{\alpha }$ and eigenmicrostate entropy $S_{\mathrm{em}}$, both derived from effective spin configurations. The control protocol dependent factor $c$ reflects the distinct ordering mechanisms and thermodynamic routes associated with each control experiment. This Letter identifies an entropy scaling framework for predicting dynamical properties of spin models using their spin configurations.

URhSn exhibits successive phase transitions at $T_{\mathrm{O}}=54\mathrm{K}$ and $T_{\mathrm{C}}=16\mathrm{K}$. While the transition at $T_{\mathrm{C}}$ is known to be ferromagnetic, the nature of the intermediate phase between $T_{\mathrm{O}}$ and $T_{\mathrm{C}}$ has remained elusive. Here, we report ${}^{117}\mathrm{Sn}$ nuclear magnetic resonance (NMR) measurements on high-quality single crystals of URhSn, which reveal NMR line splittings indicative of symmetry breaking in the intermediate phase. The field-direction and site dependences of these splittings are consistent with antiferroquadrupolar ordering characterized by the space group $P321$ (No. 150). This finding confirms the emergence of a novel form of chiral order driven by electronic degrees of freedom, without an underlying chiral crystal structure in URhSn.

Using $(10087\pm 44)\times {10}^6$ $J/\psi$ events collected with the BESIII detector at the BEPCII collider at the center-of-mass energy of $\sqrt{s}=3.097\mathrm{GeV}$, we report the first search for $\eta \to {\pi }^{0}S\to {\pi }^0\chi \overline{\chi }$ with $S$ denoting an on-shell dark scalar boson and $\chi$ an invisible dark matter particle. No significant signals are observed with $S$ mass ranging from 0 to $400\mathrm{MeV}/c^2$. The upper limits on the branching fractions and the new physics coupling strengths between $S$ and quarks are set to be $(1.8–5.5)\times {10}^{-5}$ and $(1.3–3.2)\times {10}^{-5}$ at the 90% confidence level, respectively. The constraints on the dark-matter-nucleon scattering cross section is improved by approximately five orders of magnitude over previous dark-matter-nucleon scattering experiments, providing unique insights into sub-GeV dark matter.