We study the directed transport of bosons along a one dimensional lattice in a dissipative setting, where the hopping is only facilitated by coupling to a Markovian reservoir. By combining numerical simulations with a field-theoretic analysis, we investigate the current fluctuations for this process and determine its asymptotic behavior. These findings demonstrate that dissipative bosonic transport belongs to the Kardar-Parisi-Zhang universality class and therefore, in spite of the drastic difference in the underlying particle statistics, it features the same coarse-grained behavior as the corresponding asymmetric simple exclusion process for fermions. However, crucial differences between the two processes emerge when focusing on the full counting statistics of current fluctuations. By mapping both models to the physics of fluctuating interfaces, we find that dissipative transport of bosons and fermions can be understood as surface growth and erosion processes, respectively. Within this unified description, both the similarities and discrepancies between the full counting statistics of the transport are reconciled. Beyond purely theoretical interest, these findings are relevant for experiments with cold atoms or long-lived quasiparticles in nanophotonic lattices, where such transport scenarios can be realized.

The “Tête de Moine” Swiss cheese is generally served by scraping the surface of a cylindrical loaf with a sharp tool. This produces thin sheets of cheese that are strongly wrinkled at the edge, resembling frilly flowers and enhancing the tasting experience. In this Letter we unveil the physical mechanisms at play in this scraping-induced morphogenesis. We measure the deformation of the cheese during scraping and show that plastic deformation occurs everywhere, but find a larger plastic contraction in the inner part of the flower, causing its buckling into shape. We show that it surprisingly derives from the lower friction coefficient evidenced on the cheese close to its crust. Our analysis provides the tools for a better control of flower chip morphogenesis through plasticity in the shaping of other delicacies, but also in metal cutting.

We present the first measurement of cosmic-ray fluxes of ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ isotopes in the rigidity range from 1.9 to 25 GV. The measurements are based on $9.7\times {10}^5$ ${}^6\mathrm{Li}$ and $1.04\times {10}^6$ ${}^7\mathrm{Li}$ nuclei collected by the Alpha Magnetic Spectrometer on the International Space Station from May 2011 to October 2023. We observe that over the entire rigidity range the ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ fluxes exhibit nearly identical time variations and, above $\sim 4\mathrm{GV}$, the time variations of ${}^6\mathrm{Li}$, ${}^7\mathrm{Li}$, He, Be, B, C, N, and O fluxes are identical. Above $\sim 7\mathrm{GV}$, we find an identical rigidity dependence of the ${}^6\mathrm{Li}$ and ${}^7\mathrm{Li}$ fluxes. This shows that they are both produced by collisions of heavier cosmic-ray nuclei with the interstellar medium and, in particular, excludes the existence of a sizable primary component in the ${}^7\mathrm{Li}$ flux.

We provide the first ab initio calculation of the Euclidean long-distance window of the isospin-symmetric light-quark connected contribution to the hadronic vacuum polarization for the muon $g-2$ and find $a_{\mu }^{\mathrm{LD},\mathrm{iso},\mathrm{conn},\mathrm{ud}}=411.4(4.3)(2.4)\times {10}^{-10}$. We also provide the currently most precise calculation of the total isospin-symmetric light-quark connected contribution, $a_{\mu }^{\mathrm{iso},\mathrm{conn},\mathrm{ud}}=666.2(4.3)(2.5)\times {10}^{-10}$ in the BMW20 world, which is more than $4\sigma$ larger compared to the data-driven estimates of Boito et al. [Phys. Rev. D 107, 074001 (2023)] and $1.7\sigma$ larger compared to the lattice QCD result of BMW20.

The Drosophila larva, a soft-body animal, can bend its body and roll efficiently to escape danger. However, contrary to common belief, this rolling motion is not driven by the imbalance of gravity and ground reaction forces. Through functional imaging and ablation experiments, we demonstrate that the sequential actuation of axial muscles within an appropriate range of angles is critical for generating rolling. We model the interplay between muscle contraction, hydrostatic skeleton deformation, and body-environment interactions, and systematically explain how sequential muscle actuation generates the rolling motion. Additionally, we construct a pneumatic soft robot to mimic the larval rolling strategy, successfully validating our model. This mechanics model of soft-body rolling motion not only advances the study of related neural circuits, but also holds potential for applications in soft robotics.

We study the exact maximum-likelihood decoding of quantum error-correcting codes. Our primary focus is on the repetition code under circuit-level noise, which serves as a fundamental basis for quantum error correction experiments and is the only code that has achieved large distances and extremely low error rates. We uncover that the repetition code under circuit-level noise has an exact solution and propose an optimal maximum-likelihood decoding algorithm called “planar.” This algorithm is based on the exact solution of the spin-glass partition function on planar graphs and has polynomial computational complexity. Through extensive numerical experiments, we demonstrate that our algorithm uncovers the exact threshold for depolarizing noise and realistic superconductor SI1000 noise. Furthermore, we apply our method to analyze data from recent quantum memory experiments conducted by Google Quantum AI, revealing that part of the error floor was attributed to the decoding algorithm used by Google. Finally, we implemented the repetition code quantum memory on superconducting systems using a 72-qubit quantum chip lacking reset gates, demonstrating that even with an unknown error model, the proposed algorithm achieves a significantly lower logical error rate than the matching-based algorithm. We also discuss the application of our approach to quantum codes whose maximum-likelihood decoding problem corresponds to a spin-glass problem, including the surface code under independent code-capacity noise.

Electrical control of magnetism promises potential applications in low-cost, high-density spintronic devices; however, it remains a great challenge in traditional multiferroics. Here we propose that a type-III multiferroic material, where magnetism is driven by ferroelectricity, can be used to achieve effective electrical control of magnetism. We reveal that the emergence of ferroelectricity in a low-dimensional system could significantly reduce the interatomic orbital overlap and narrow the electronic bands, which increases the Stoner instability and, thus, results in a transition from nonmagnetic to ferromagnetic states. Based on first-principles calculations, the ferroelectricity-driven magnetism is demonstrated in a two-dimensional ${\mathrm{InI}}_3$ monolayer adsorbed by Cu single atoms (denoted as $\mathrm{Cu}\text{−}{\mathrm{InI}}_3$). When an out-of-plane shift of the Cu atom induces an out-of-plane ferroelectricity, the system is transferred from a nonmagnetic to a ferromagnetic phase. The revealed type-III multiferroics and electrical control of magnetism offer an innovative strategy for developing multiferroic and magnetoelectric devices.

We present a novel candidate for cold dark matter consisting of condensed Cooper pairs in a theory of interacting fermions with broken chiral symmetry. Establishing the thermal history from the early radiation era to the present, the fermions are shown to behave like standard radiation at high temperatures, but then experience a critical era decaying faster than radiation, akin to freeze-out, which sets the relic abundance. Through a second-order phase transition, fermion-antifermion pairs condense and the system asymptotes toward zero temperature and pressure. By the present era, the nonrelativistic, massive condensate decays slightly faster than in the standard scenario–a unique prediction that may be tested by combined measurements of the cosmic microwave background and large scale structure. We also show that in the case of massive fermions, the phase transition is frustrated, and instead leaves a residual, long-lived source of dark energy.

We demonstrate nonreciprocal control of the speed of light by sending a microwave pulse through a cavity magnonics device. In contrast to reciprocal group velocity controlled by conventional electromagnetically induced transparency (EIT) effects, incorporating a dissipative magnon-photon coupling establishes a nonreciprocal EIT effect, allowing slow and fast light propagation in opposite directions at the same frequency with comparable amplitude. Remarkably, reversing the magnetic field enables a directional switch between nonreciprocal fast and slow light. This discovery may offer new possibilities for pulse time regulation in microwave signal communications, neuromorphic computing, and quantum signal processing.

An entanglement purification protocol (EPP) aims to transform multiple noisy entangled states into a single entangled state with higher fidelity. In this work we consider input-independent EPPs that always yield an output fidelity no worse than each of the original noisy states, a property we call universality. We prove there is no $n$-to-1 EPP implementable by local operations and classical communication that is universal for all two-qubit entangled states, whereas such an EPP is possible using more general positive partial transpose-preserving (PPT) operations. We also show that universality is impossible by any bilocal Clifford EPP even when restricted to states with fidelities above an arbitrarily high threshold.

We report a remarkable enhancement of superconductivity near the Anderson metal-insulator transition in the three-dimensional (3D) BCS-superconductor bismuth selenide (BiSe). The SnSe-type orthorhombic BiSe is successfully stabilized upon decompression after this phase is formed at high pressure from the two-dimensional layered BiSe phase and the intrinsic disorder concomitantly approaches the localization threshold near ambient pressure. A dramatic enhancement of the superconducting transition temperature near the localization transition is associated with the sharp increase in the local density of states and significant increase in the background dielectric constant, hence providing a short-ranged Coulomb interaction. This study, for the first time, validates the theoretical formulation for the superconductivity enhancement in a 3D system near localization and demonstrates the novel compression-decompression route to induce high homogeneous disorder.

A novel localization phenomenon, termed erratic non-Hermitian skin localization, has been identified in disordered globally reciprocal non-Hermitian lattices. Unlike conventional non-Hermitian skin effect and Anderson localization, it features macroscopic eigenstate localization at irregular, disorder-dependent positions with subexponential decay. Using the Hatano-Nelson model with disordered imaginary gauge fields as a case study, this effect is linked to stochastic interfaces governed by the universal order statistics of random walks. Finite-size scaling analysis confirms the localized nature of the eigenstates. This discovery challenges conventional wave localization paradigms, offering new avenues for understanding and controlling localization phenomena in non-Hermitian physics.

Non-Hermitian photonics revolutionizes the understanding and manipulation of wave propagation in open systems. However, due to the interplay of non-Hermitian light-matter interactions and complex long-range couplings, miniaturizing topological features into deep-subwavelength regimes remains a significant challenge, and state-of-the-art explorations have thus far remained on the reciprocal topological photonic states. Here, we introduce nonreciprocal surface waves into deep-subwavelength dimerized lattices to theoretically demonstrate an efficient thermophotonic funnel. The system comprises an array of silicon carbide nanoparticles coupled with a graphene substrate. Under electrical bias, the graphene substrate enables the breaking of time-reversal symmetry in a magnetic-free and compact configuration, while also providing additional channels for photonic-based heat flow. The synergy between nonreciprocal surface waves and collective thermophotonic interactions drives all eigenstates to collapse toward the truncation of the lattice, exhibiting up to a 278-fold enhancement in one-way radiative field intensity. The topological fingerprints of this funneling effect are characterized by point-gap topology and complex-eigenspectrum braiding. Our findings bridge non-Hermitian physics and nonreciprocal thermophotonics, unlocking new possibilities for topological applications.

Long baseline diffraction-limited optical aperture synthesis technology by interferometry plays an important role in scientific study and practical application. In contrast to amplitude (phase) interferometry, intensity interferometry—which exploits the second-order coherence of thermal light—is robust against atmospheric turbulence and optical defects. However, a thermal light source typically has a broadband spectrum, a low average photon number per mode, and a wide divergence angle, forestalling extended applications. Here, we propose and demonstrate active intensity interferometry for optical synthetic aperture imaging over the kilometer range. Our scheme employs multiple phase-independent laser emitters to generate thermal illumination and utilizes a flexible computational algorithm for image reconstruction. Through outdoor experiments, we have successfully imaged millimeter-scale targets located at 1.36 km away, achieving a resolution enhancement by about 14 times over the diffraction limit of a single telescope. The application of long-baseline active intensity interferometry holds promise for advancing high-resolution optical imaging and sensing.

Solid-state quantum sensors based on ensembles of nitrogen-vacancy (NV) centers in diamond have emerged as powerful tools for precise sensing applications. Nuclear spin sensors are particularly well suited for applications requiring long coherence times, such as inertial sensing, but remain underexplored due to control complexity and limited optical readout efficiency. In this work, we propose cooperative cavity quantum electrodynamic (cQED) coupling to achieve efficient nuclear spin readout. Unlike previous cQED methods used to enhance electron spin readout, here we employ two-field interference in the NV hyperfine subspace to directly probe the nuclear spin transitions. We model the nuclear spin NV-cQED system (nNV-cQED) and observe several distinct regimes, including electromagnetically induced transparency, masing without inversion, and oscillatory behavior. We then evaluate the nNV-cQED system as an inertial sensor, indicating a rotation sensitivity improved by 3 orders of magnitude compared to previous solid-state spin demonstrations. Furthermore, we show that the NV electron spin can be simultaneously used as a comagnetometer, and the four crystallographic axes of NVs can be employed for vector resolution in a single nNV-cQED system. These results showcase the applications of two-field interference using the nNV-cQED platform, providing critical insights into the manipulation and control of quantum states in hybrid NV systems and unlocking new possibilities for high-performance quantum sensing.

${}^4\mathrm{He}$ nanodroplets doped with an alkali ion feature a snowball of crystallized layers surrounded by superfluid helium. For large droplets, we predict that a transitional supersolid layer can form, bridging between the solid core and the liquid bulk, where the ${}^4\mathrm{He}$ density displays modulations of icosahedral group symmetry. To identify the different phases, we combine density functional theory with the semiclassical Gaussian time-dependent Hartree method for localized many-body systems. This hybrid approach can handle large particle numbers and provides insight into the physical origin of the supersolid layer. For small droplets, we verify that the predictions of our approach are in excellent agreement with Path-Integral Monte Carlo calculations.

We study a spherically confined mixture of polymers and colloidal rings. Unlike in standard colloid-polymer mixtures, the polymers interact topologically with the rings by threading them. We find that, above a critical value of the ring radius, threading yields a topological transition from a fluid to a gel-like phase characterized by a space-spanning network of interlocked polymers and rings, which we refer to as a bicomponent gel, or bigel. By exploiting the mixture dual character (rings and polymers), we predict analytically the value of the critical radius. We also show that the mobility of entanglements in the mixture slows down upon entering the gel phase, due to topological hindrance arising from threadings, while the transition rates between topological states of the colloidal probes provide another strong dynamical signature of the gel phase.

Fusion plasma regimes with a strongly radiating magnetic $X$ point are promising candidates to tackle the outstanding power exhaust challenge in reactor-scale devices. In this Letter, we report on a new type of $X$-point radiator, the XPTR ($X$-point target radiator), produced by a secondary $X$ point placed well away from the confined plasma. This XPTR features strongly facilitated detachment access and significantly reduced sensitivity of the radiative front position near the secondary $X$ point. Consistent with a reduced analytical model, the physical origin of $X$-point radiation is rooted in its magnetic geometry, irrespective of whether the field lines are closed or open. The results presented open up a class of novel power exhaust concepts where radiative edge cooling can be robustly avoided during divertor detachment.

By confining colloidal active fluids in microchannel networks, we demonstrate that their degenerate flows correspond to the configurations of the six-vertex model. We use this quantitative correspondence to control and explain the active flows that emerge in square-grid networks. In particular, we show that the Lagrangian trajectories of active particles realize the Baxter-Kelland-Wu mapping and form completely packed loops, whose geometry can be exactly predicted and explained. We then go beyond the square-grid geometry and introduce a general framework for predicting the geometry of active-hydraulic flows in arbitrary networks.

We study dynamical gravitational collapse in a theory with an infinite tower of higher-derivative corrections to the Einstein-Hilbert action and we show that, under very general conditions, it leads to the formation of regular black holes. Our results are facilitated by the use of a class of theories that possess second-order equations on spherically symmetric metrics, but which are general enough to provide a basis for the gravitational effective action in any $D\ge 5$. We analytically solve the collapse of a thin shell of dust and show that it inevitably experiences a bounce at small radius and that its motion can be extended to arbitrary proper time. The collapse of the shell always gives rise to a singularity-free, geodesically complete spacetime that contains horizons if the total mass is above a critical value. In that case, the shell bounces into a new universe through a white hole explosion. Our construction provides, to the best of our knowledge, the first fully dynamical description of formation of regular black holes, and it suggests that higher-derivative corrections may be the most natural way to resolve the singularities of Einstein’s theory.