Leveraging complementary machine-learning-based approaches, we compute properties of $s$- and $p$-shell $\mathrm{\Lambda }$ hypernuclei—including binding energies, single-particle densities, and radii—starting from the individual interactions among their constituents. These interactions are modeled based on a leading-order finite-cutoff pionless effective field theory expansion. The couplings and the range of the three-nucleon and $\mathrm{\Lambda }$-nucleon-nucleon potentials are determined via a Gaussian process framework anchored on virtually exact few-body techniques. We solve the many-body Schrödinger equation using a variational Monte Carlo method based on neural network quantum states, extending it for the first time to include $\mathrm{\Lambda }$ particles alongside protons and neutrons. The predicted binding energies show remarkably good agreement with experimental results, given the simplicity of the input Hamiltonian. We also confirm the experimentally observed shrinkage of the proton radius in ${}_{\mathrm{\Lambda }}{}^7\mathrm{Li}$ compared to its parent nucleus, ${}^6\mathrm{Li}$. This work paves the way for an ab initio description of medium-mass and heavy hypernuclei, which is critical for understanding the onset of strange degrees of freedom in the core of neutron stars.

We study a spinful, time-reversal symmetric lowest Landau level model for a flatband quantum spin Hall system at total filling fraction ${\nu }_{\mathrm{T}}=2/3$. Such models are relevant, e.g., for spin-valley locked moiré transition metal dichalcogenides. The opposite Chern number of the two spins hinders the formation of a quantum Hall ferromagnet, instead favoring other phases. We study the phase diagram in dependence on different short-range Haldane pseudopotentials $v_m$ and uncover several phases: a fractional topological insulator, a phase-separated state, a spin-polarized fractional quantum Hall state, and the partially particle-hole transformed Halperin (111) state. The effect of the pseudopotentials $v_m$ depends on the parity of $m$, the relative angular momentum.

Here, we demonstrate that vacuum fluctuations can induce lateral forces on a small particle positioned near a translation-invariant uniform non-Hermitian substrate with chiral gain. This type of non-Hermitian response can be engineered by biasing a low-symmetry conductor with a static electric field and is rooted in the quantum geometry of the material through the Berry curvature dipole. The chiral-gain material acts as an active medium for a particular circular polarization handedness, while serving as a passive, dissipative medium for the other polarization handedness. Owing to the nonreciprocity and gain characteristics, momentum is continuously exchanged in a preferred direction parallel to the surface between the test particle and the surrounding electromagnetic field, giving rise to lateral forces. Interestingly, the force can be viewed as a fluctuation-induced drag analogous to a Hall force. Indeed, although the gain is driven by an electric current, the resulting force acts perpendicular to the bias—unlike conventional current-drag effects. This effect stems from the skewed propagation characteristics of surface modes and gain-momentum locking. Our theory reveals a Hall-like asymmetry in the field correlations and establishes a link between quantum geometry and fluctuation-induced phenomena, offering possibilities for nanoscale control via tailored electromagnetic environments.

In this paper, we theoretically and experimentally analyze sequential processors with limited communication between parts. We compare the expressivity of sequential quantum and classical processors under the same constraints. They consist of three or four modules, each of which processes local data. The modules of the quantum processor are linked through one-qubit or one-qutrit communication, while those of the classical processor communicate through one bit or one trit. For the classical processor, we prove bounds on its performance in terms of inequalities on correlations of the output with a target function. We theoretically show that the quantum processor violates these inequalities. We show this violation experimentally on a silicon photonics setup. We describe how to find the classical bound on correlations with arbitrary target function by reducing the problem to the minimization of an Ising-type spin-glass Hamiltonian. Our theory is applicable to general problems, such as the low-rank binary matrix approximation.

We present a systematic study of interchannel quantum interference in laser-induced nonsequential double ionization within the strong-field approximation. Focusing on the below-threshold intensity regime where the recollision excitation with subsequent ionization (RESI) pathway dominates, we derive analytical phase conditions governing interference between distinct excitation channels for arbitrary driving fields. To quantify the interplay between channels resulting from a vast number of interfering processes, we introduce statistical metrics based on the earth mover's distance, allowing us to assess the relative weight of each channel's contribution to the two-electron photoelectron momentum distributions. We identify key factors that determine whether interchannel interference is appreciable, such as comparable channel intensities, strong spatial overlap between the excited-state wave functions, and the energy difference between contributing channels. We demonstrate that for linearly polarized few-cycle pulses, the typical intrachannel interference features associated with exchange, temporal shifts, and combined exchange-temporal interference are retained with interchannel interference. Our findings establish a hierarchy of interference mechanisms in RESI and may provide practical guidelines for enhancing or suppressing interference in different regions of the momentum plane. The tool kit presented in this work is transferable to a wide range of interferometric schemes involving different excitation channels.

In this work, we introduce a superconducting quantum processor architecture that uses a transmission-line resonator to implement effective all-to-all connectivity between six transmon qubits. This architecture can be used as a test bed for algorithms that benefit from high connectivity. We show that the central resonator can be used as a computational element, which offers the flexibility to encode a qubit for quantum computation or to utilize its bosonic modes that further enables quantum simulation of bosonic systems. To operate the quantum processing unit (QPU), we develop and benchmark the qubit-resonator conditional $Z$ gate and the qubit-resonator MOVE operation. The latter allows for transferring a quantum state between one of the peripheral qubits and the computational resonator. We benchmark the QPU performance and achieve a genuinely multiqubit entangled Greenberger-Horne-Zeilinger state over all six qubits with a readout-error mitigated fidelity of $F_{{|\psi \rangle }_{\mathrm{GHZ}}}=0.86$.

The framework of bipartite stochastic thermodynamics is a powerful tool to analyze a composite system's internal thermodynamics. It has been used to study the components of different molecular machines such as ATP synthase. However, this approach has not yet been used to describe ion-transporting proteins despite their high-level functional similarity. Here, we study the bipartite thermodynamics of the sodium-potassium pump in the nonequilibrium steady state. Using a physically intuitive partition between the ATP-consuming subsystem and the ion-transporting subsystem, we find considerable information flow comparable to other molecular machines, and Maxwell-demon behavior in the ATP-consuming subsystem. We vary ion concentrations and transmembrane voltage in a range including the neuronal action potential, and find that the information flow inverts during depolarization.

Rydberg antiblockade, or facilitation, governs interaction-assisted excitation dynamics that generate a wide variety of collective phenomena and correlated many-body behavior, while also forming the basis of protocols for entangling gates, state transfer, and quantum sensing. Despite its rich physics, experimental realization of facilitation has been fragile because the resonance condition requires precise matching between interaction shifts and laser detuning, making the process highly sensitive to atomic position disorder and parameter fluctuations. To overcome this limitation, we develop a robust implementation of Rydberg facilitation based on rapid adiabatic passage. By adiabatically sweeping the laser detuning across the interaction-shifted resonance, our approach is inherently insensitive to typical experimental imperfections. As a direct demonstration, we show that this adiabatically protected facilitation naturally gives rise to avalanche excitation growth in both one- and two-dimensional arrays. This avalanche process yields high gain with exceptionally low background, making it promising for rare-event detection. More broadly, by completely eliminating disorder sensitivity, our approach transforms Rydberg facilitation from an experimentally elusive regime into a robust mechanism implementable with standard cooling techniques and existing optical tweezer platforms, bridging the gap between theoretical proposals and disorder-free experimental realizations of antiblockade-based quantum control.

Probabilistic entangling measurements are key operations in linear-optical quantum technologies, enabling the generation and manipulation of high-dimensional quantum states. While prior research has focused predominantly on specific entangled states, notably graph states and Greenberger-Horne-Zeilinger (GHZ) states, broader classes of states with variable entanglement remain underexplored. In this work, we present a linear-optical approach for generating and fusing GHZ-like states, which generalize standard GHZ states to include variable entanglement degrees. We introduce two schemes based on modified fusion gates that allow flexible control over generation efficiency and the entanglement of the output states. These results offer a promising pathway toward resource-efficient entangled-state generation for scalable quantum computing and communication.

Sharing entangled pairs between nonsignaling parties via entanglement swapping constitutes a striking demonstration of the nonlocality of quantum mechanics and a crucial building block for future quantum technologies. In this work, we generalize pair-swapping methods by introducing a many-body entanglement swapping protocol, which allows two nonsignaling parties to share general many-body states along an arbitrary partitioning. The shared many-body state retains exactly the same Schmidt vectors as the target state and exhibits typically high fidelity, which approaches unity as the variance of the Schmidt coefficients vanishes. Moreover, we demonstrate how the three-party protocol can be generalized to many-body swapping networks, enabling a general many-body state sharing with unit fidelity via arbitrary number of intermediate nodes. This is achieved by replacing all but one of the unitary operations with those corresponding to the same Schmidt states but with a flattened spectrum, which also completely eliminates the need for postselection. We provide a proof of concept of the three-party protocol on real quantum hardware and discuss how it enables functionalities, such as fault-tolerant entanglement swapping and strategies for distributed quantum computing.

The intricate fine structure of Kikuchi diffraction plays a vital role in probing phase transformations and strain distributions in functional materials, particularly in electron microscopy. Beyond these applications, it also proves essential in photoemission spectroscopy (PES) at high photon energies, aiding in the disentanglement of complex angle-resolved PES data and enabling emitter-site-specific studies. However, the detection and analysis of these rich faint structures in photoelectron diffraction, especially in the hard x-ray regime, remain highly challenging, with only a limited number of simulations successfully reproducing these patterns. The strong energy dependence of Kikuchi patterns further complicates their interpretation, necessitating advanced theoretical approaches. To enhance structural analysis, we present a comprehensive theoretical study of fine diffraction patterns and their evolution with energy by simulating core-level emissions from Ge(100) and Si(100). Using multiple-scattering theory and the fully relativistic one-step photoemission model, we simulate faint pattern networks for various core levels across different kinetic energies (106–4174 eV), avoiding cluster size convergence issues inherent in cluster-based methods. Broadening in patterns is discussed via the inelastic scattering treatment. For the first time, circular dichroism has been observed and successfully reproduced in the angular distribution of Si(100) $1s$, revealing detailed features and asymmetries up to 31%. Notably, we successfully replicate experimental bulk and more “surface-sensitivity” diffraction features, further validating the robustness of our simulations. The results show remarkable agreement with the experimental data obtained using circularly polarized radiations, demonstrating the potential of this methodology for advancing high-energy PES investigations.

Understanding and mitigating noise in quantum systems is a fundamental challenge in achieving scalable and fault-tolerant quantum computation. Error modeling for quantum systems can be formulated in many ways, some of which are very fundamental, but hard to analyze (evolution by general dynamical map) and others perhaps too simplistic to represent physical reality. In this paper, we present an intermediate approach, introducing the random Schrödinger equation, with a noise term given by a time-varying random Hermitian matrix as a means to model noisy quantum systems. We derive bounds on the error of the synthesized unitary in terms of bounds on the norm of the noise, and show that for certain noise processes these bounds are tight. We then show that in certain situations, minimizing the error is equivalent to finding a geodesic on $\mathrm{SU}\left(n\right)$ with respect to a Riemannian metric encoding the coupling between the control pulse and the noise process, thus connecting our work to the complexity geometry pioneered by Michael Nielsen.

We provide a general framework for the quantization of light-matter theories with time-dependent holonomic constraints. Unless time dependence is present from the outset at the Lagrangian level, different gauges generally produce nonequivalent canonical theories. The irrotational gauge is defined as the one that also yields a correct theory when time dependence is introduced at the Hamiltonian level. Our framework unifies examples of such gauges found in existing literature. In particular, we show that for describing time-dependent light-matter interactions the Coulomb gauge is not generally irrotational, so it does not enjoy any special status.

Neural quantum states (NQSs) are powerful variational ansätze capable of representing highly entangled quantum many-body wavefunctions. While the average entanglement properties of ensembles of restricted Boltzmann machines are well understood, the entanglement structure of autoregressive NQSs such as recurrent neural networks and transformers remains largely unexplored. We perform large-scale simulations of ensembles of random autoregressive wavefunctions for chains of up to 256 spins and uncover signatures of transitions in their average entanglement scaling, entanglement spectra, and correlation functions. We show that the standard softmax normalization of the wavefunction suppresses entanglement and fluctuations, and introduce a square modulus normalization function that restores them. Finally, we connect the insights gained from our entanglement and activation function analysis to initialization strategies for finding the ground states of strongly correlated Hamiltonians via variational Monte Carlo.

The melting of two-dimensional monocrystals is described within the celebrated Kosterlitz‐Thouless‐Halperin‐Nelson‐Young scenario by the dissociation of topological defects. It describes the screening of elasticity due to thermally activated topological defects until shear elasticity disappears. As a well-defined continuous phase transition, freezing and melting should be reversible and independent of history. However, this is not the case: Cooling an isotropic two-dimensional fluid at a finite but nonzero rate does not result in monocrystals. The symmetry cannot be broken globally but only locally within Einstein's event horizon: The slowing down of critical fluctuations forces the system to fall out of equilibrium, resulting in finite-sized domains with a uniform order parameter. For linear cooling rates, the domain size is described by the Kibble‐Zurek mechanism, originally developed for defect formation in the primordial Higgs field shortly after the Big Bang. The size of the domains is a function of the so-called fallout time, the time when the ensemble becomes nonergodic. In the present manuscript, we go beyond the Kibble‐Zurek picture and investigate the limit of the deepest quench on a colloidal monolayer. We resolve the time dependence of structure formation for (local) symmetry breaking when the fallout time is effectively set to zero. However, when quenching instantaneously to various temperatures below the melting point—either deep in the crystalline phase or close to the transition—we find universal behavior if the timescale is rescaled properly.

Insects rely on their hearing in order to communicate, identify and locate potential mates, and avoid predators. Due to their small sizes, many insect species are not able to use the interaural time and intensity differences employed by vertebrates for the localization of sound, but have instead evolved other mechanisms to perform this task. One such mechanism is the antenna, which provides directionally sensitive acoustic information. In contrast to tympanic ears, which detect scalar pressure fields, antennal ears detect the vector-valued velocity fields of sound. We argue that this detection scheme at small length scales, combined with the dipolelike radiation of sound emitted from flying insects, results in short ranges of detection. These short ranges imply that the acoustic signals transmitted between two insects flying past each other will be brief and rapidly changing with time, presenting a challenge in extracting precise frequency information. However, this frequency information has been shown to be essential for insects to identify and locate potential mates. In the current work, we propose potential mechanisms that insects may employ in order to extract precise frequency and directional information from these transient signals, thereby circumventing the apparent limitations.

Angle-resolved photoemission spectroscopy (ARPES) is a widely used characterization technique in condensed matter physics, providing direct access to the single-electron spectral function of crystals, including their electronic band structure and Fermi surface. Measuring the band structure of novel quantum materials has been fundamentally important for determining, for example, nontrivial band topology, as in topological insulators, Weyl semimetals, and Dirac semimetals, or for identifying new classes of materials, such as altermagnets. A key challenge with these emerging quantum materials is that their initial crystalline quality is rarely optimized, which directly affects the spectra measured by ARPES. Here, we present a theoretical framework and experimental evidence addressing two common consequences of static disorder in photoemission experiments: the loss of coherent spectral weight and the broadening of spectral features. ARPES spectra can be understood as a sum of coherent and incoherent intensities, with their relative contributions controlled by atomic disorder and electron correlation effects. For disorder caused by phonons, the coherent intensity is exponentially suppressed as temperature increases, a phenomenon analogous to the Debye-Waller factor in diffraction, where Bragg peaks diminish in favor of diffuse scattering as disorder increases. In this work, we report a soft-x-ray study of the deliberately disordered (via Ar ion sputtering) InAs(110) surface, characterized by scanning tunneling microscopy, scanning tunneling spectroscopy, and low-energy electron diffraction. We introduce a framework that enables quantification of coherent photoemission intensity loss with increasing disorder, allowing both thermal and static disorder to be treated within a unified approach. Additionally, we identify a second major effect of disorder beyond lifetime broadening: inhomogeneous spectral broadening arising from local potential fluctuations. We show that such fluctuations increase the linewidths of the spectra of localized and delocalized states and contribute to the suppression of ARPES intensity from states near the Fermi level. The concepts and analysis methods presented should make ARPES useful for direct diagnosis of disorder effects on electronic states, for science as well as engineering.

Heterogeneous diffusion processes (HDPs) are ubiquitous in macromolecules or submicron tracers in biological cells. The Fokker-Planck equation (FPE) provides a fundamental framework for analyzing these diffusion dynamics. However, its formulations for HDPs with spatially dependent diffusivity are not unique, which can lead to potentially divergent dynamical predictions. We investigate three conventional interpretations (Itô, Stratonovich, and Hänggi-Klimontovich) of FPEs describing two-dimensional diffusion processes with power-law spatially dependent diffusivity. Through analytical solutions of time-dependent probability density functions, which are validated by numerical simulations, we reveal significant interpretation-dependent discrepancies in several physical quantities. These include distinct temporal evolution of mean-square displacement (MSD), survival probabilities, and threshold times at which half of the particles reach a set boundary. Furthermore, we demonstrate that the mean of time-averaged MSDs varies across different interpretations, yielding distinct effective diffusion coefficients. This offers a chance to identify the applicable interpretation by comparing theoretical effective diffusion coefficients with those extracted from single-particle tracking experiments. Our findings reveal that the appropriate interpretation could depend on measurement timescales and system's parameters. We believe that these results are helpful for investigating diffusion dynamics in complex heterogeneous environments.