Gauge fields are ubiquitous in modern quantum physics. In superfluids, quantized vortices can be induced by gauge fields. Here we demonstrate the first experimental observation of vortex nucleations in light-dressed spinor Bose-Einstein condensates under radially localized synthetic magnetic fields. The light-induced spin-orbital-angular-momentum coupling creates azimuthal gauge potentials $\overrightarrow{A}$ for the lowest-energy spinor branch dressed eigenstate. The observation of the atomic wave function in the lowest-energy dressed eigenstate reveals that vortices nucleate from the cloud center of a vortex-free state with canonical momentum $\overrightarrow{p}=0$. This is because a large circulating azimuthal velocity field $\propto \overrightarrow{p}-\overrightarrow{A}$ at the condensate center results in a dynamically unstable localized excitation that initiates vortex nucleations. Furthermore, the long-time dynamics to reach the ground state stops in a metastable state when $|\overrightarrow{A}|$ is not sufficiently large. Our observation has reasonable agreement with the time-dependent Gross-Pitaevskii simulations.

We argue that stochastic and resonant ion heating, often viewed as distinct processes in low-$\beta$ collisionless plasmas, are the far limits of a continuum controlled by nonlinear broadening of turbulent fluctuations, and thus by the normalized cross helicity. We propose a simple empirical formula that captures both regimes, generalizing the model commonly used to describe stochastic heating. Simulations of test ions interacting with turbulence confirm our scalings across a wide range of different ion and turbulence properties, including with a steep ion-kinetic transition range as seen in the solar wind. Our results provide a unified framework for understanding ion heating processes across diverse astrophysical environments from black-hole accretion disks to the solar corona, also providing a compact and versatile subgrid model for larger-scale simulations.

Quantum sensing with nitrogen-vacancy (NV) centers in diamond enables the characterization of magnetic properties in the extreme situation of a tiny sample with defects. Recent studies have reported superconductivity in ${\mathrm{La}}_3{\mathrm{Ni}}_2{\mathrm{O}}_{7\text{−}\delta }$ under pressure, with zero resistance near 80 K, though the Meissner effect remains debated due to low superconducting volume fractions and limited high-pressure magnetic measurement techniques. In this work, we use diamond quantum sensors and four-probe detection to observe both zero resistance and the Meissner effect in the same ${\mathrm{La}}_3{\mathrm{Ni}}_2{\mathrm{O}}_{7\text{−}\delta }$ single crystal. By mapping the Meissner effect, we visualized superconducting regions and revealed sample inhomogeneities. Our combined magnetic and electrical measurements on the same crystal provide dual evidence of superconductivity, supporting the high-temperature superconductivity of ${\mathrm{La}}_3{\mathrm{Ni}}_2{\mathrm{O}}_{7\text{−}\delta }$. This study also offers insights into its structural and magnetic properties under high pressure.

We study the electronic structure of bulk $1{\mathrm{T}\text{−}\mathrm{TaSe}}_2$ in the charge-density wave phase at low temperature. Our spatially and angle-resolved photoemission data show insulating areas coexisting with metallic regions characterized by a chiral Fermi surface and moderately correlated quasiparticle bands. Additionally, high-resolution laser angle-resolved photoemission reveals variations in the metallic regions, with series of low-energy states, whose energy, number, and dispersion can be explained by the formation of quantum well states of different thicknesses. Dynamical mean field theory calculations show that the observed rich behavior can be rationalized by assuming occasional stacking faults of the charge density wave. Our results indicate that the diverse electronic phenomena reported previously in $1{\mathrm{T}\text{−}\mathrm{TaSe}}_2$ are dictated by the stacking arrangement and the resulting quantum size effects while correlation effects play a secondary role.

Helimagnets exhibit noncollinear spin arrangements characterized by a periodic helical modulation, giving rise to emergent chiral properties. These materials have attracted significant interest due to their potential applications in spintronics, particularly for robust information storage and the realization of topological spin textures such as skyrmions. In this work, we focus on Yoshimori-type helimagnets, where competing exchange interactions mediated by conduction electrons stabilize helical spin structures without requiring Dzyaloshinskii-Moriya interaction. We introduce a minimal model describing the electronic structure of a one-dimensional helimagnet in the presence of an external magnetic field and investigate its impact on nonreciprocal transport. We demonstrate how band asymmetry emerges in the conical phase induced by the external field, leading to a nonzero second-order electronic conductivity and injection photoconductivity. Our results provide insight into the interplay between the real space magnetic texture and electronic properties, paving the way for future studies on chirality-driven transport phenomena in centrosymmetric helimagnets.

Monitored quantum circuits have attracted significant interest as an example of synthetic quantum matter, intrinsically defined by their quantum information content. Here, we propose a multipartite entanglement perspective on monitored phases through the lens of quantum Fisher information. Our findings reveal that unstructured monitored random circuits fail to exhibit divergent multipartite entanglement even at criticality, highlighting their departure from standard quantum critical behavior. However, we demonstrate that genuinely multipartite entangled phases can be realized through two-site measurements, provided a protection mechanism is in place. This work positions multipartite entanglement as a valuable perspective for the study of interacting monitored circuits and broader frameworks of noisy quantum dynamics.

Quantum computing is expected to provide an exponential speedup in machine learning. However, optimizing the data loading process, commonly referred to as “quantum data embedding,” to maximize classification performance remains a critical challenge. In this Letter, we propose a neural quantum embedding (NQE) technique based on deterministic quantum computation with one qubit (DQC1). Unlike the traditional embedding approach, NQE trains a neural network to maximize the trace distance between quantum states corresponding to different categories of classical data. Furthermore, training is efficiently achieved using DQC1, which is specifically designed for ensemble quantum systems, such as nuclear magnetic resonance (NMR). We validate the NQE-DQC1 protocol by encoding handwritten images into NMR quantum processors, demonstrating a significant improvement in distinguishability compared to traditional methods. Additionally, after training the NQE, we implement a parametrized quantum circuit for classification tasks, achieving 98% classification accuracy, in contrast to the 54% accuracy obtained using traditional embedding. Moreover, we show that the NQE-DQC1 protocol is extendable, enabling the use of the NMR system for NQE training due to its high compatibility with DQC1, while subsequent machine learning tasks can be performed on other physical platforms, such as superconducting circuits. Our Letter opens new avenues for utilizing ensemble quantum systems for efficient classical data embedding into quantum registers.

We consider correlation functions of two maximal giant gravitons and two light $\frac{1}{2}$-BPS (Bogomol’nyi–Prasad–Sommerfield) operators in 4D $\mathcal{N}=4$ SYM (super Yang-Mills). Viewed as two-point correlators in the presence of a zero-dimensional defect, they can be completely fixed at strong coupling using analytic bootstrap techniques. We determine all infinitely such correlators for arbitrary light $\frac{1}{2}$-BPS operators and find that the result can be repackaged into a simple generating function thanks to a hidden higher-dimensional symmetry. We also find evidence that the same symmetry holds at weak coupling for loop correction integrands.

We present a new measurement of the $2\nu \beta \beta$ half-life of ${}^{130}\mathrm{Te}$ ($T_{1/2}^{2\nu }$) using the first complete model of the CUORE data, based on 1038 kg yr of collected exposure. Thanks to optimized data selection, we achieve a factor of two improvement in precision, obtaining $T_{1/2}^{2\nu }=(9.32{}_{-0.04}^{+0.05}\mathrm{stat}{}_{-0.07}^{+0.07}\mathrm{syst})\times {10}^{20}\mathrm{yr}$. The signal-to-background ratio is increased by 70% compared to our previous results, enabling the first application of the improved $2\nu \beta \beta$ formalism to ${}^{130}\mathrm{Te}$. Within this framework, we determine a credibility interval for the effective axial coupling in the nuclear medium as a function of nuclear matrix elements. We also extract values for the higher-order nuclear matrix element ratios: second-to-first and third-to-first. The second-to-first ratio agrees with nuclear model predictions, while the third-to-first ratio deviates from theoretical expectations. These findings provide essential tests of nuclear models and key inputs for future $0\nu \beta \beta$ searches.

Exceptional rings (ERs) are high-dimensional non-Hermitian topologies formed by exceptional points, significantly enriching the topological properties of non-Hermitian systems. Because of the intricate topology and symmetry requirements, the realization of ERs generally demands complex structures and precise parameter tuning, resulting in relatively few experimental observations in high-dimensional periodic systems. Here, we show that even the simplest 1D non-Hermitian periodic systems can support multiple ERs, enabled by the system’s multiple degrees of freedom which naturally accommodate diverse non-Hermitian perturbations. The proposed system can host one to four ERs as well as hybrid ER by simply tuning the non-Hermitian loss, with a bulk Fermi torus in momentum space serving as the fundamental origin of this tunability. Through experiments using 1D perovskite photonic crystals, we observe the ERs associated bulk Fermi torus at visible frequencies. Our work establishes a simple platform for realizing complex non-Hermitian topologies, enabling optical-frequency applications harnessing non-Hermitian physics.

The photonic flat band, defined by minimal dispersion and near-zero group velocity, has facilitated significant advances in optical technologies. The practical applications of flat bands, such as enhanced light-matter interactions, require efficient coupling to far-field radiation. However, achieving controlled coupling between flat bands and their corresponding localized modes with far-field radiation remains challenging and elusive. Here, we achieve the tunable far-field excitation of a flat band in the near-infrared spectral range by coupling it to a photonic anapole mode. Distinct from conventional multipolar resonances in both its physical nature and unique radiation dynamics, the anapole mode offers highly localized field distributions and tunable emission characteristics, enabling the realization of a photonic flat band and precise control over its transition from a nonradiative to a radiative state. We directly observed the flat band within $\pm 25°$ experimentally by angle-resolved far-field transmissivity spectroscopy. Simulation results extending to 90° confirm the persistence of the band’s flatness across all incident angles, validating the inherent flatness of the band. Our findings not only provide a viable approach to accessing photonic flat bands but also significantly advance the field of nanoscale photonic manipulation, offering broad potential applications in optical technologies.

The coupling of lasers plays an important role in a variety of research activities, from generating high-power lasers to investigating out-of-equilibrium coupled systems. This Letter presents our investigations of Hermitian coupling in arrays of lasers, where it is possible to control both the amplitude and phase of the coupling and generate artificial gauge fields. The Hermitian coupling is demonstrated in three laser array geometries: a square array of 100 lasers with controlled laser coupling for obtaining continuous control over the phase-locked state, a triangular array of 130 lasers with controlled chirality of the lasers, and a ring array of eight lasers with a controlled topological charge. In the square array, we implemented arbitrary laser coupling with a precision of $2\pi /120$ radians, enabling the attainment of arbitrary phase-locking states. In the triangular array, we controlled the chirality of the lasers with 99% purity. In the ring array, the introduction of an artificial gauge field revealed discrete quantized first-order transitions between distinct topological phase-locking states. The results pave the way for exploring spin systems with programmable coupling in an all-optical spin simulator.

The doped topological insulator ${\mathrm{Cu}}_x{\mathrm{Bi}}_2{\mathrm{Se}}_3$ has attracted considerable attention as a new platform for studying novel properties of spin-triplet and topological superconductivity. In this work, we performed synchrotron x-ray diffraction measurements on ${\mathrm{Cu}}_x{\mathrm{Bi}}_2{\mathrm{Se}}_3$ ($0.24\le x\le 0.46$) to investigate the coupling between the superconducting order parameter and crystal lattice. In the crystals in which the vector order parameter ($\mathit{d}$ vector) is tilted from the crystal high-symmetry directions as evidenced by nematic diamagnetic susceptibility, we find a sizable lattice distortion ($\sim 100\mathrm{pp}\mathrm{m}$) associated with the onset of superconductivity. In contrast, in crystals with the $\mathit{d}$ vector aligned along the high-symmetry directions, we find no appreciable change in lattice constant. Together with a pronounced vestigial behavior of the distortion, the results are clear evidence for an odd-parity $E_u$ order parameter that couples with trigonal lattice. Furthermore, in the crystal with $x=0.46$ where diamagnetic susceptibility is isotropic in the plane, no lattice distortion accompanying the superconducting transition is found, which is in line with a chiral superconducting state in the highly doped region. Our work shows that lattice distortion can be a powerful diagnosing quantity for nematic superconductivity with two-component order parameter.

We show that the ground state of a weakly charged two-dimensional electron-hole fluid in a strong magnetic field is a broken translation symmetry state with interpenetrating lattices of localized vortices and antivortices in the electron-hole-pair field. The vortices and antivortices carry fractional charges of equal sign but unequal magnitude and have a honeycomb-lattice structure that contrasts with the triangular lattices of superconducting electron-electron-pair vortex lattices. We predict that increasing charge density or a weakening magnetic field drives a vortex delocalization transition that would be signaled experimentally by an abrupt increase in counterflow transport resistance.

We address the problem of identifying a $2+1\mathrm{D}$ topologically ordered phase using measurements on the ground-state wave function. For nonchiral topological order, we describe a series of bulk multipartite entanglement measures that extract the invariants ${\sum }_a{d}_a^2{\theta }_a^r$ for any $r\ge 2$, where $d_a$ and ${\theta }_a$ are the quantum dimension and topological spin of an anyon $a$, respectively. These invariants are obtained as expectation values of permutation operators between $2r$ replicas of the wave function, applying different permutations on four distinct regions of the plane. Our proposed measures provide a refined tool for distinguishing topological phases, capturing information beyond conventional entanglement measures such as the topological entanglement entropy. We argue that any operator capable of extracting the above invariants must act on at least $2r$ replicas, making our procedure optimal in terms of the required number of replicas. We discuss the generalization of our results to chiral states.

Multilayer networks provide a powerful framework for modeling complex systems that capture different types of interactions between the same set of entities across multiple layers. Core-periphery detection involves partitioning the nodes of a network into core nodes, which are highly connected across the network, and peripheral nodes, which are densely connected to the core but sparsely connected among themselves. In this paper, we propose a new model of core-periphery structure in multilayer networks and a nonlinear spectral method that simultaneously detects the corresponding core and periphery structures of both nodes and layers in weighted and directed multilayer networks. Our method reveals novel structural insights in three empirical multilayer networks from distinct application areas: the citation network of complex network scientists, the European airlines transport network, and the world trade network.

Interlocked and polycatenated material systems, consisting of discrete, nonconvex particles linked to their nearest neighbors, such as chainmail fabrics, have been shown to undergo a jamming transition that increases their rigidity under boundary compression. This rigidity transition is associated with an increase in contact number between particles. In architected materials, rigidity is described by theories such as the Maxwell criterion. In this Letter, we propose a rigidity theory for a type of interlocked material system: the torus knot tessellation. Torus knot tessellations are structured fabrics composed of particles shaped as torus knots. In these fabrics, we theoretically demonstrate that in-plane rigidity is governed by a modified Maxwell criterion, while out-of-plane rigidity is governed by a crease line criterion. These theories provide a framework for the design of rigidity of these fabrics.