High-order perfect absorption of coherent input has recently attracted significant attention due to its broadband absorption capacity. However, the realization of a high-order perfect absorber relies on the exceptional point (EP) to coalesce the scattering zeros. Here, we present a general scattering framework and achieve the high-order perfect absorber in the absence of an EP. We consider the asynchronous coherent input, where a spatial delay introduces a momentum-dependent phase factor beyond the amplitude and phase control in synchronous coherent input. This new degree of freedom enables active control of the momentum-dependent output, effectively reshaping the absorption line shape necessary for the high-order perfect absorber. Remarkably, despite the absence of an EP, the proposed high-order perfect absorber exhibits significant response to the perturbations in the delay length. Our findings provide insights for the delay-induced momentum-sensitive interference phenomenon and offer a new route for wave control.

Light-matter interactions can be substantially altered in the presence of time-varying media. We study the interaction between a harmonic electric dipole and a plasmonic time crystal slab. Temporal modulation of the plasma frequency enables near-field gain, allowing the dipole to absorb rather than emit energy, suppressing nonradiative losses. At the parametric resonance condition, the slab radiates strongly to the far field, producing 100% oscillations in the radiated power at distances up to ${10}^3$ times the $\epsilon$-near-zero wavelength. These findings reveal a new mechanism for controlling light-matter interaction in time-varying plasmonic systems.

Understanding and predicting how complex systems respond to external perturbations is a central challenge in nonequilibrium statistical physics. Here, we consider continuous-time Markov networks, which we subject to perturbations along a single edge. We find that in steady state the probabilities of any two states are linearly related to one another. We show that this mutual linearity of probabilities extends to a broad class of observables, including currents but also generic counting and state-dependent observables. Moreover, we derive an exact relation between the relative response of any state’s probability and the ratio of two steady-state probabilities. Leveraging the Markov chain tree theorem, we further show that probabilities and the considered observables are constrained by the topological and kinetic properties of the network and provide analytical expressions in terms of spanning tree polynomials. Our results are general, holding for arbitrary rate parametrizations and extending far from equilibrium.

We develop a first-principles theory for the vibrational density of states (VDOS) and thermal properties of network materials built on stationary correlated disordered point configurations. For elastic networks with stretching and bending interactions, we show that the empirical spectral measure of the vector dynamical matrix converges in the thermodynamic limit to the pushforward of Lebesgue measure under longitudinal and transverse Fourier symbols, which depend only on the edge kernels and the two-point statistics of the underlying point set. For disordered hyperuniform systems in the stretching-dominant regime, we showed that hyperuniformity does not alter the leading Debye exponent but suppresses sample-to-sample fluctuations, yielding a smooth, crystal-like acoustic edge. For bending-dominant systems with hyperuniform scaling $S(k)\sim k^{\alpha }$, the VDOS exhibits an algebraic pseudogap at low frequency, $g(\omega )\sim {\omega }^{2d/\beta -1}$ with $\beta =\min \{4,\alpha +2\}$, which implies a low-temperature specific heat $C(T)\sim T^{2d/\beta }$ and a heat-kernel decay $Z(t)\sim t^{-d/\beta }$, defining a spectral dimension $d_s=2d/\beta$. This hyperuniformity-induced algebraic edge depletion could enable novel wave manipulation and low-temperature applications.

We present an experimental and theoretical study of 2-D swarms in which collective behavior emerges from both direct local mechanical coupling between agents and from the exchange and processing of information between agents. Each agent, an air-table drone endowed with internal memory and a binary decision variable, updates its state by integrating a time series of memories of local past collisions. This internal computation transforms the swarm into a dynamical information network in which history-dependent feedback drives spontaneous complete spin polarization, pitchfork bifurcated spin collectives, and chaotic switching between collective states. By tuning the depth of memory and the decision algorithm, we uncover a memory-induced phase transition that breaks spin symmetry at the population level. A minimal theoretical model maps these dynamics onto an effective potential landscape sculpted by informational feedback, revealing how temporally correlated computation can replace instantaneous forces as the driver of collective organization, informed by experiments. These results position physically interacting drone swarms as a model system for exploring the physics of informational drone ensembles whose emergent behavior arises from the interplay between physical interaction and information processing.

A semianalytical model for the evolution of galaxies and supermassive black holes within the cold dark matter paradigm has been shown to yield stellar-black hole mass relations that reproduce both the James Webb Space Telescope and pre-Webb telescope observations. Either fuzzy or warm dark matter would suppress the formation of the smaller galactic halos that play important roles in the cold dark matter fit to the high-redshift supermassive black hole data. Our analysis of the stellar-black hole mass relation disfavors fuzzy dark matter fields with masses $<2.0\times {10}^{-20}\mathrm{eV}$ and warm dark matter particles with masses $<7.2\mathrm{keV}$, both at the 95% confidence level.

Nuclear quantum effects (NQEs) significantly influence many fundamental physical and chemical phenomena. However, their impact on ultrafast dynamics remains poorly understood. Here, we demonstrate that solid-state high-harmonic generation (HHG) provides a promising platform for probing NQEs in attosecond processes. In particular, NQEs substantially modify HHG trajectories due to charge density ripples (CDR) induced by nuclear quantum delocalization. Incorporating NQE-modulated CDR shifts the oscillation phase of HHG, and thus introduces special properties and measurable signatures in the harmonic features, including the emission symmetry and rotation angle of the harmonic polarization ellipse, providing a plausible explanation for recent experimental observations. These findings enable all-optical detection of NQE-driven charge fluctuations via HHG spectroscopy.

We derive a quantum extension of the thermodynamic uncertainty relation where dynamical fluctuations are quantified by the Terletsky–Margenau–Hill quasiprobability, a quantum generalization of the classical joint probability. The obtained inequality plays a complementary role to existing quantum thermodynamic uncertainty relations, focusing on observables’ change rather than exchange of charges through jumps and respecting initial coherence. Quasiprobabilities show anomalous behaviors that are forbidden in classical systems, such as negativity; we reveal that negativity or a nonclassically enhanced escape rate is necessary to increase an output-to-dissipation ratio beyond classical limitations and show that the requirements are basis independent and stronger than quantum coherence. To illustrate these statements, we employ a model that can exhibit a dissipationless heat current, which would be prohibited in classical systems; we construct a state that has much coherence but does not lead to a dissipationless current due to the absence of anomalous behaviors in quasiprobabilities.

In quantum field theory (QFT), the “vacuum” is not just empty space but the lowest-energy state of a quantum field. If the energy landscape has multiple local minima, the local ground states are the false vacuum (FV) which can tunnel toward the global ground state (true vacuum, TV). This process exhibits signature akin to classical supercooled gas transitions and many-body tunneling in discrete quantum systems. Here, we study the FV decay and bubble nucleation in a Rydberg atom ring. The $1/r^6$ van der Waals interactions and individual-site addressability allow us to explore physics beyond the standard Ising model. We observe that the FV decay rate decreases exponentially with the inverse of the symmetry-breaking field, directly mirroring QFT predictions. Moreover, we demonstrate that even minor deviations from the ideal metastable state can cause a stark departure from this universal scaling law. Extending beyond short-time decay dynamics, we also examine resonant bubble nucleation, a feature distinctive to systems with discrete energy spectra. Our findings and methods open avenues for future studies of many-body tunneling in higher dimensions or more complex geometries.

According to the ER $=$ EPR conjecture, entangled particles are connected by quantum wormholes. Under the assumption that some of the electric field surrounding an entangled charged particle leaks into the wormhole, we show that this effect will modify the hyperfine structure of the hydrogen atom. In addition, if the quantum wormholes are nontraversable, this will also lead to a nonzero total effective charge for the hydrogen atom. These effects provide strong constraints on the amplitude of this potential ER $=$ EPR effect, given high-precision measurements of the hydrogen atom’s hyperfine structure and total charge.

We present MicroBooNE’s first search for dark sector $e^{+}{e}^{-}$ explanations of the long-standing MiniBooNE anomaly. The MiniBooNE anomaly has garnered significant attention over the past 20 years including previous MicroBooNE investigations into both anomalous electron and photon excesses, but its origin still remains unclear. In this Letter, we provide the first direct test of dark sector models in which dark neutrinos, produced through neutrino-induced scattering, decay into missing energy and visible $e^{+}{e}^{-}$ pairs comprising the MiniBooNE anomaly. Many such models have recently gained traction as a viable solution to the anomaly while evading past bounds. Using an exposure of $6.87\times {10}^{20}$ protons-on-target in the Booster Neutrino Beam, we implement a selection targeting forward-going, coherently produced $e^{+}{e}^{-}$ events. After unblinding, we observe 95 events, which we compare with the constrained background-only prediction of $69.7\pm 17.3$. This analysis sets the world’s first direct limits on these dark sector models and, at the 95% confidence level, excludes the entirety of the single dark neutrino and majority of the dual dark neutrino, parameter space that is viable as a solution to the MiniBooNE anomaly.

The question of whether interactions can break dynamical localization in quantum kicked rotor systems has been the subject of a long-standing debate. Here, we introduce an extended mapping from the kicked Lieb-Liniger model to a high-dimensional lattice model and reveal universal features: on-site pseudorandomness and hybrid exponential-algebraic decay couplings with increasing momenta. We find that the exponent and the amplitude of the algebraic decay undergo a crossover as the interaction strength increases. This mapping uncovers the origin of dynamical localization and the interaction effect on the integrability of the system. An analysis of the generalized fractal dimension and level-spacing ratio supports these findings, highlighting the presence of near integrability and multifractality in different regions of parameter space. Our results offer an explanation for the occurrence of many-body dynamical localization, particularly in strongly correlated quantum gases, and are anticipated to generalize to systems of many particles.

The emergence of breathing solitons in mode-locked lasers presents a fundamental challenge for the theoretical modeling of mode locking, with the mechanisms underlying below- and above-threshold breathing solitons, and the origins of their distinct nonlinear dynamics, remaining poorly understood. Here, we develop a model that incorporates both spatial and temporal gain dynamics, enabling us to elucidate the origins of these two classes of pulsating states. We show that below-threshold breathing solitons arise from the interplay between Q switching and soliton shaping, whereas Kerr nonlinearity and dispersion dominate the formation of above-threshold breathers. The model further captures the markedly different dynamical properties of these regimes. Experimental observations corroborate the simulations, validating the predictive power of the framework. Beyond providing a refined theoretical basis for ultrafast laser design, this Letter advances the broader understanding of nonequilibrium dynamics in mode-locked lasers and offers new perspectives on breathing soliton phenomena across diverse physical systems.

We develop the theory of antisymmetric Raman response, defined as the difference between the Raman signals of two scattering geometries related by an exchange of mutually perpendicular incoming and the outgoing photon polarizations. Such responses, finite in orthorhombic or lower symmetry systems, are related to cross-susceptibilities of two Raman operators and are characterized by the absence of intraband terms. This is in contrast to standard Raman responses which measure auto-susceptibilities where both intra- and interband processes contribute. We illustrate the theory with examples from the charge density wave rare-earth tritellurides and the excitonic insulator ${\mathrm{Ta}}_2{\mathrm{NiSe}}_5$. Our theory establishes antisymmetric Raman response as a unique tool to probe microscopic features such as interband energy scales and to detect reflection symmetry breaking.

The ultrafast magnetization dynamics of an epitaxial $\mathrm{Fe}/\mathrm{CoO}$ bilayer on Ag(001) is examined in an element-resolved way by resonant soft-x-ray reflectivity. The transient magnetic linear dichroism at the Co $L_2$ edge and the magnetic circular dichroism at the Fe $L_3$ edge measured in reflection in a pump–probe experiment with 120 fs temporal resolution show the loss of antiferromagnetic and ferromagnetic order in CoO and Fe, respectively, both within 300 fs after excitation with 60 fs light pulses of 800 and 400 nm wavelengths. A comparison to spin-dynamics simulations using an atomistic spin model shows that direct energy transfer from the laser-excited electrons in Fe to the magnetic moments in CoO provides the dominant demagnetization channel in the case of 800-nm excitation.