Single photons are the flying qubits of choice for distributing entanglement in a quantum internet. Quantum memories embedded in quantum repeaters are crucial to overcome transmission loss and enhance the rate of quantum communication. A multimode memory can further boost the channel capacity. However, benchmarking and building a practical quantum memory that simultaneously optimizes multiple performance metrics poses two key challenges. Here, we introduce quantum interconnect rate to comprehensively quantify quantum memories, and further demonstrate a high-performance quantum memory that simultaneously integrates three essential criteria at once: large multimode capacity, high efficiency, and high fidelity. Operating on 11-dimensional spatial modes, our memory achieves a uniform efficiency exceeding 80% and qubit storage fidelities above 99%, enabling the efficient storage of high-dimensional qudits. Based on these capabilities, we estimate a distribution of $3.56\pm 0.16\mathrm{bits}$ of quantum information over a 1000-km repeater link in one minute, highlighting a practical pathway toward scalable quantum interconnects and quantum networks.

Long-distance matter-matter entanglement is pivotal for scalable quantum communication, distributed quantum computing, and sensing. In this Letter, we report entanglement between two atomic ensemble quantum memories over 420 km. We employ the Duan-Lukin-Cirac-Zoller (DLCZ) scheme for remote entanglement generation and convert photons emitted from the memories to telecom S band that enable us to harness ultralow transmission loss in fiber. We stabilize a photon’s relative phase between the two memories using full-time far-off-resonant locking to reduce high-frequency noise and intermittent dual-band locking to compensate low-frequency drift jointly. Furthermore, we demonstrate that the memory-memory entangling probability beats the repeaterless channel capacity for direct entanglement distribution. Our experiment provides a test bed of studying quantum network applications beyond metropolitan scale.

Twisted graphene provides a tunable platform for studying superconductivity in two dimensions. In the presence of electric currents and magnetic fields, vortices determine the phenomenological properties of the material. Here, we employ a gate-defined Josephson junction as a single-vortex sensor, enabling direct access to individual vortex dynamical events. Our measurements reveal that vortices enter the superconducting leads via classical thermal activation over energy barriers at elevated temperatures $T>100\mathrm{mK}$. At low temperatures $T<90\mathrm{mK}$, we observe macroscopic quantum tunneling through these barriers. The data are consistent with a sharp, first-order type quantum-to-classical transition. From our measurements, we extract vortex entry and exit energy barriers on the order of a few kelvins and estimate the barrier thickness to be approximately 100 nm.

The exceptional tunability of two-dimensional van der Waals materials offers unique opportunities for exploring novel superconducting phases. However, in such systems, the measurement of superfluid phase stiffness, a fundamental property of a superconductor, is challenging because of the mesoscopic sample size. Here, we introduce a contact-free technique for probing the electrodynamic response, and thereby the phase stiffness, of atomically thin superconductors using on-chip superconducting microwave resonators. We demonstrate this technique on $4\mathrm{Hb}\text{−}{\mathrm{TaS}}_2$, a van der Waals superconductor whose gap structure under broken mirror symmetry is under debate. In our cleanest few-layer device, we observe a superconducting critical temperature comparable to that of the bulk. The temperature evolution of the phase stiffness features nodeless behavior in the presence of broken mirror symmetry, inconsistent with the scenario of nodal surface superconductivity. With minimal fabrication requirements, our technique enables microwave measurements across wide ranges of two-dimensional superconductors.

Large twist angles in twisted bilayer graphene are widely expected to be electronically trivial, with negligible interlayer coupling and no electronic reconstruction, in contrast to the rich moiré-driven band reconstruction and correlated physics that emerge at small twist angles. Here, we show that this paradigm breaks down near a twist angle of 29°, where the system crosses over between quasicrystalline and commensurate order. Atomic-resolution transmission electron microscopy directly reveals the coexistence of near-dodecagonal quasicrystalline symmetry and emerging moiré periodicity, indicating an intermediate, nonperiodic structural regime. Magnetotransport measurements uncover strong interlayer hybridization mediated by Umklapp scattering, manifested by magneto-intersubband oscillations and a highly unconventional Landau-level spectrum. Remarkably, the Landau-level degeneracy evolves from 4- to 12-fold with increasing temperature, a behavior incompatible with two decoupled graphene monolayers. These findings establish large-angle twisted bilayer graphene as a platform where quasiperiodic symmetry fundamentally reshapes low-energy electronic states beyond the conventional moiré framework.

We obtain an exact analytic expression for the dynamical structure factor of one-dimensional quantum gas of hard rods. Our result is valid for an arbitrary many-body state of the system, with finite temperature states and the ground state being important special cases that we analyze in detail. We demonstrate that the expression obeys fundamental relations such like the $f$-sum rule and the detailed balance. We also reveal the hidden fermionic structure behind the correlator. In the static limit we show that it can be written in terms of universal functions, which, at zero temperature, coincide with the level spacing distribution function of the Gaussian unitary ensemble. Our Letter provides a full and exact characterization of a dynamic correlation function in a strongly correlated interacting quantum many-body system.

Axion quasiparticles introduce magnetoelectric coupling in topological materials, yet their optical signatures are intrinsically weak, severely limiting experimental detection and practical exploitation. Here, we demonstrate maximal optical chirality of axion quasiparticles by coupling them with degenerate quasibound states in the continuum (qBICs). By integrating three-dimensional topological insulators (3DTIs) with achiral photonic crystal slabs (PCSs), we reveal that axion quasiparticles induce an effective Zeeman effect that lifts the degeneracy of achiral qBICs in PCSs, splitting them into two nondegenerate high-$Q$ chiral qBICs with maximally opposite chirality. These result in a more than ${10}^3$- and 200-fold increase in the polarization conversion efficiency and Faraday rotation angle, respectively, compared to the intrinsic chiroptical response of bare 3DTI films. Moreover, circular dichroism and nonreciprocal optical responses are revealed as new key signatures for probing axion quasiparticles in 3DTI-PCS coupled systems. Our results provide a definitive route for observing axion quasiparticles and topological physics, while establishing a promising platform for controlling optical polarization, spin, phase, and nonreciprocal responses.

Rare events refer to qualitatively unlikely events whose realization can nevertheless have important consequences. Typically, the prediction of the kinetics of these events relies on Arrhenius laws, with exponentially distributed waiting times, and no correlations between successive occurrences. However, this description breaks down in the presence of long-term memory, as has been observed in the contexts of geophysical time series or protein dynamics. So far, existing analytical approaches do not quantify the correlations between rare events due to long-term memory. Here, for non-Markovian Gaussian processes, we determine analytically the impact of long-term memory on the distribution of first and second passage times to a rarely reached threshold, using a perturbation approach. This distribution is nonexponential, thus going beyond the Arrhenius paradigm. We obtain an explicit expression for the covariance between the first and second passage times, and we predict how the mean time to the next extreme event depends on the previous passage time, illustrating the phenomenon of clustering of extreme events. These analytical results, validated through extensive stochastic simulations, shed lights on the strong correlation between successive occurrences of extreme events due to long-term memory.

Quantum communication protocols seek to leverage the unique properties of quantum systems for coordination or communication tasks, usually with guarantees of security or anonymity that exceed what is possible classically. One promising domain of application is elections, where strong such guarantees are essential to ensure legitimacy. We experimentally implement a recently proposed election protocol from Centrone et al. [Quantum protocol for electronic voting without election authorities, Phys. Rev. Appl. 18, 014005 (2022)] designed such that no one, including a potential central authority, can know the preferred candidate of any voter other than themself. We conduct a four-party election, generating and distributing four-partite GHZ states with $\approx 89\%$ fidelity and successfully recording voters’ intentions $\approx 87\%$ of the time.

Quantum information protocols offer significant advantages in properties such as security, anonymity, and privacy for communication and computing tasks. An application in which guaranteeing the highest possible security and privacy is critical for democratic societies is electronic voting. As computational power continues to evolve, classical voting schemes may become increasingly vulnerable to information leakage. In this Letter, we present the experimental demonstration of an information-theoretically-secure and efficient electronic voting protocol that, crucially, does not rely on election authorities, leveraging the unique properties of quantum states. Our experiment is based on a high-performance source of Greenberger-Horne-Zeilinger (GHZ) states and realizes a proof-of-principle implementation of the protocol in two scenarios: a configuration with four voters and two candidates employing privacy enhancement techniques and an election scenario supporting up to eight voters and 16 candidates. The latter is particularly well suited for secure board-level elections within organizations or small-scale governmental contexts.

A long-standing issue for fusion reactors based on 3D magnetic confinement (stellarators) has been finding suitable coils. Traditional optimization methods struggle to balance multiple physics and engineering constraints, requiring significant computing resources and input tuning, yet still resulting in suboptimal or infeasible configurations. We present a new optimization method based on an augmented Lagrangian scheme and show that it efficiently generates stellarator coils that exhibit enhanced physics performance and meet essential design requirements. This will accelerate progress toward commercially viable stellarator fusion reactors.

Weather extremes pose major societal risks, especially in a changing climate, but due to their rarity, they are difficult to study using limited observations or complex climate models. We introduce $\mathrm{AI}+\mathrm{RES}$, a framework coupling fast AI weather forecasts with a high-fidelity physics model using a rare-event algorithm to efficiently characterize extremes. This approach enables the study of the statistics and physics of very rare events, such as once per millennium heat waves at two orders-of-magnitude lower computational cost. $\mathrm{AI}+\mathrm{RES}$ can be applied broadly across climate science and other fields concerned with rare events.

We investigate thickness-dependent charge-density-wave (CDW) transitions in $1T\text{−}{\text{TaS}}_2$ using temperature-dependent Raman spectroscopy and electrical transport. Raman measurements show that the incommensurate, nearly commensurate, and commensurate CDW phases persist down to the monolayer limit. As the thickness is reduced, the transition temperatures increase, accompanied by an orders-of-magnitude rise in sheet resistance and a sharp reduction in the carrier localization length. The first-order hysteretic commensurate CDW to nearly commensurate CDW transition is uniquely absent in the monolayer. Calculations suggest that the enhanced CDW in thin layers originates from strengthened Coulomb interactions due to reduced out-of-plane screening, particularly in the nonlocal component. These findings highlight the cooperative roles of electron correlation, electron-phonon interaction, and interlayer coupling in shaping the ground state and transition dynamics of atomically thin $1T\text{−}{\text{TaS}}_2$, opening pathways for engineering correlated phases in two-dimensional CDW systems.

Neutrino emission from nuclear reactors provides real-time insights into reactor power and fuel evolution, with potential applications in monitoring and nuclear safeguards. Following reactor shutdown, a low-intensity flux of “residual neutrinos” persists due to the decay of long-lived fission isotopes in the partially burnt fuel remaining within the reactor cores and in spent nuclear fuel stored in nearby cooling pools. The Double Chooz experiment at the Chooz B nuclear power plant in France achieved the first quantitative measurement of this residual flux based on 17.2 days of reactor-off data. In the energy range where the residual signal is most pronounced, the neutrino detector located 400 m from the cores recorded $106\pm 18$ neutrino candidate events ($5.9\sigma$ significance). This measurement is in excellent agreement with the predicted value of $88\pm 7$ events derived from detailed reactor simulations modeling the decay activities of fission products and incorporating the best-available models of neutrino spectra.

Neutral atom arrays have emerged as a powerful platform for quantum computation, simulation, and metrology. Among them, alkaline-earth-like atoms exhibit distinct advantages, including long coherence time, high-fidelity Rydberg gates, and erasure correction for efficient quantum error correction. However, their scalability has lagged behind that of the alkali atoms. Here, we report 2400 ytterbium-174 atoms trapped in an optical tweezer array with enhanced loading efficiency of 83.5(1)% via blue-detuned light-assisted collisions. We develop a quantitative model of the collision dynamics and find good agreement between the calculated inelastic collision rates and the experimentally measured loading efficiencies. Notably, the loading efficiency is largely maintained for array sizes ranging from dozens to thousands, exhibiting excellent scalability. We further demonstrate that the enhancement exists robustly across a range of interatomic potentials, suggesting its utility for other atomic species. To establish the capability of the ${}^{174}\mathrm{Yb}$ arrays toward universal quantum computation, we propose to encode the qubit in the ground-clock state manifold and estimate a 99.9% two-qubit gate fidelity with experimentally feasible parameters. Our work advances the prospects for realizing large-scale quantum computers using alkaline-earth-like atoms.

Emergent gauge fields and Coulomb liquids have long been central to the physics of frustrated pyrochlore magnets, yet their realization beyond conventional, i.e., rank-one U(1), spin ice and into fully quantum higher-rank regimes has remained elusive. Here we provide strong evidence for this physics in the spin-$\frac{1}{2}$ quantum Heisenberg antiferromagnet on the breathing pyrochlore lattice with symmetry-allowed Dzyaloshinskii-Moriya interactions, using the pseudofermion functional renormalization group. We find a robust quantum analog of the rank-one U(1) Coulomb liquid together with compelling signatures of a putative quantum analog of the rank-two U(1) Coulomb liquid, distinguished by their characteristic multifold pinch-point morphologies in momentum space. This Letter therefore establishes a minimal three-dimensional setting in which signatures of gauge theories of different rank emerge within a single microscopic spin Hamiltonian. In addition, quantum fluctuations qualitatively reshape the classical nearest-neighbor atlas of phases, causing an incommensurate spiral instability and an extended nondipolar quantum paramagnetic regime, both absent in the classical model. Our results establish the breathing pyrochlore as a promising and experimentally relevant platform where higher-rank gauge constraints, conventional magnetic order, and fluctuation-driven quantum phases compete on equal footing, opening a direct route to diagnosing emergent gauge structure in three-dimensional quantum magnets.

We propose the sublattice currents in a compensated collinear magnetic system as a feasible route to odd-parity altermagnetism (ALM), where nonrelativistic collinear spin splitting occurs in the bands as an odd function of momentum. In contrast to previously classified ALMs, the sublattice currents break the time-reversal symmetry in the nonmagnetic crystal structure and allow for such odd-parity spin splitting. A representative example is the Haldane-Hubbard model at half filling. Although the compensated collinear magnetic ground state was previously recognized as antiferromagnetism, we show that it is actually an odd-parity ALM. Interestingly, its topological version serves as an example of an ALM Chern insulator. We further generalize the Haldane-Hubbard model to common two- and three-dimensional bipartite lattices. With spin splitting allowed by sublattice currents, the compensated collinear magnetic ground states at half filling are generally odd-parity ALM.

Quarks and gluons, as quantum particles, are subject to various effects that go beyond the naive parton picture and are not captured by ordinary parton densities. In this work, we investigate the twist-three parton distribution functions, which encode quantum interference between quark-gluon-quark states, and for the first time, determine them directly from experimental data. The analysis combines observables described by collinear and transverse-momentum–dependent factorization theorems within a unified global fit, incorporating a complete leading-order QCD evolution at the twist-three level. The extracted distributions reveal clear flavor-dependent patterns and are distinct from zero at a statistically significant level ($2-3\sigma$). These findings provide the first quantitative evidence for quark-gluon-quark correlations within the proton, revealing its genuinely quantum nature and opening a new direction for precision studies of partonic correlations.

The Landau rainbow offers a promising way for advanced multiplexed wave processing. However, current Landau rainbows are restricted with narrow $k$-space range of flat Landau levels. Meanwhile, given the promise of rainbow trapping for developing multiplexed elastic devices in integrated phononic networks, the realization of flat Landau rainbow in elastic systems—particularly in the ultrasonic regime—remains highly desirable. Here, we realize megahertz Landau rainbows in an elastic metamaterial by artificially synthesizing both pseudomagnetic fields (PMFs) and pseudoelectric fields (PEFs). Importantly, nonuniform PMFs are introduced to enhance the $k$-space range of the flat zeroth Landau levels that form the Landau rainbow. Multiplexed megahertz ultrasonic energy trappings enabled by the Landau rainbow are directly visualized via laser scanning technology, which agree well with the simulation results. Moreover, the unique field distributions of such Landau rainbows are shown to result from the mode profiles of the Landau levels with different group velocities. Our Letter not only offers a new recipe for engineering the Landau rainbow from Landau levels with enhanced flatness, but also paves the way for the development of elastic integrated devices with multiplexed wave preprocessing capacities.

The control of elastic waves on a chip is essential for next-generation signal processing and integrated acoustics. In this Letter, we experimentally demonstrate an on-chip elastic-wave rainbow capture effect. A topological rainbow emerges by introducing pseudomagnetic field and pseudoelectric fields through structural modulation, where the elastic Landau level modes of different frequencies are spatially separated at distinct positions on the same chip. Interestingly, such bulk rainbow can be captured by the topological chiral edge states originated from the pseudo-magnetic field. We directly measure the rainbow distribution and the ensuing rainbow capture of elastic waves in a silicon-based phononic chip. Our Letter establishes a functional bridge between the bulk rainbow and topological edge states, offering new possibilities for designing the multifrequency devices of elastic waves.