Non-Hermitian physics has drawn tremendous attention in both fundamental physics and potential applications. Recent progress has witnessed a surge of research on non-Hermitian skin effects (NHSEs), where wave dynamics exhibits unconventional behaviors like non-Hermitian amplifications/attenuations, sticky effects, and edge bursts. In previous studies, the dynamics of NHSEs was often treated as the propagation of a single wavepacket. Here, we provide a novel perspective by exploring the multiwavepacket dynamics of NHSEs. This is realized by introducing nonreciprocal long-range couplings into the non-Hermitian Hatano-Nelson (HN) model. It is shown that by tuning the coupling strengths based on the periodic boundary condition (PBC) spectrum, the emergence, number, propagation directions, and intensities of multiple wavepackets in the bulk can be effectively controlled. Based on the open boundary condition (OBC) spectrum, the full temporal evolution and physical origins of the non-Hermitian wavepackets can be exactly captured. The PBC and OBC spectra complement each other, enabling both flexible manipulation and rigorous interpretation of multiple wavepackets, forming a complete theoretical framework for NHSE multiwavepacket dynamics. Furthermore, beyond using the stationary spectrum to understand and control multiwavepacket dynamics, we elucidate the time-dependent excitation methods for manipulating the relative intensity of different wavepackets in systems with and without loss. In particular, we identify the crucial role of the real part of the excitation frequency in selectively exciting different wavepackets. Our results reveal the rich dynamic properties of NHSEs and offer new insights for non-Hermitian wave manipulations in both spatial and temporal domains.

The production and evolution of radiation damage constitute a complex, multiscale process involving a wide range of physical mechanisms. Since electronic stopping represents the primary channel for energy dissipation by high-energy ions, it can be reasonably inferred that electrons play a significant role in high-energy irradiation damage cascades. This fundamental perspective, however, has largely overlooked the role of electronic effects in the regime of low-energy radiation damage. Moreover, the scarcity of reliable electronic stopping data for low-energy ions further hinders the investigation of electronic effects in low-energy radiation damage. This research combines real-time time-dependent density functional theory for electron dynamics with molecular dynamics simulations of collision cascades to examine the multiscale characteristics of irradiation damage. The basic molecular dynamics model, along with its extensions, the electronic energy loss model and the two-temperature model, are employed to explore the roles of electronic stopping and electron-phonon coupling during the collision cascade and in the resulting defects surviving. We show the respective roles of electronic stopping and electron-phonon coupling in shaping the defects produced by low-energy irradiation damage.

The pursuit of high-speed, low-power spintronic devices has driven extensive research into the anomalous Hall effect (AHE) in antiferromagnets. Concurrently, the topological Hall effect (THE), a hallmark of chiral spin textures, has emerged as a critical probe of nontrivial magnetism. Here, we report the synthesis and physical properties of ${\mathrm{V}}_{1/4}{\mathrm{NbSe}}_2$, a centrosymmetric van der Waals antiferromagnet with a $2\times 2$ superlattice structure. It exhibits two successive antiferromagnetic (AFM) transitions: a paramagnetic-to-AFM1 transition at $T_N$ = 14.7 K, followed by an AFM1-to-AFM2 transition below $T_t\approx$ 6.4 K. Magnetic characterization reveals dominant AFM interactions, weak magnetocrystalline anisotropy, and nonlinear magnetization suggestive of a spin-flop-like transition. Electrical transport demonstrates coexisting AHE and THE phenomena. The AHE, which is likely dominated by the intrinsic mechanism, peaks near $T_N$ with a conductivity of $\sim 160$ ${\mathrm{\Omega }}^{-1}{\mathrm{cm}}^{-1}$. Notably, the THE emerges exclusively within the AFM2 phase, suggesting its origin of a field-induced nonzero scalar spin chirality. Magnetoresistance exhibits butterfly-shaped hysteresis loops stemming from spin-dependent electron scattering. These phenomena collectively point to an intricate magnetic ground state in the absence of Dzyaloshinskii-Moriya interaction, warranting further investigation to unravel the underlying spin configuration.

Precise control of emergent magnetic monopoles in artificial spin ice is pivotal for topological spin-based circuitry. We model a square-ice lattice on a “rotating squares” kirigami scaffold, so a single mechanical rotation angle $\theta$ reprograms dipolar couplings. Monte Carlo simulations and analytic results show $\theta$ not only drives a specific type of Dirac string tension through zero, reverses bound monopole motion, but also slows down and collimates the collective motion of multiple monopoles along nearly straight strings. The cut-and-fold design is based on a geometric principle that is inherently scale- and material-independent, offering a versatile route to reconfigurable ‘‘magnetricity’’ devices; the specific magnetic functionality, however, is determined by the chosen material and dimensions.

We propose a disorder-free one-dimensional single-particle Hamiltonian hosting an exact mobility edge (ME), placing the system outside the assumptions of no-go theorems regarding unbounded potentials. By applying a linear Stark potential selectively to one sublattice of a dimerized chain, we generate an effective Hamiltonian with unbounded, staggered hopping amplitudes. The unbounded nature of the hopping places the model outside the scope of the Simon-Spencer theorem, while the staggered scaling allows it to evade broader constraints on Jacobi matrices. We analytically derive the bulk spectrum in reciprocal space, identifying a sharp ME where the energy magnitude equals the intercell hopping strength. This edge separates a continuum of extended states from two distinct localized branches: a standard unbounded Wannier-Stark ladder and an anomalous bounded branch accumulating at the ME. The existence of extended states is supported by finite-size scaling of the inverse participation ratio up to system sizes $L\sim {10}^9$. Furthermore, we propose an experimental realization using photonic frequency synthetic dimensions. Our numerical results indicate that the ME is robust against potential experimental imperfections, including frequency detuning errors and photon loss, establishing a practical path for observing MEs in disorder-free systems.

The existence of Anderson localization, characterized by vanishing diffusion due to strong disorder, has been demonstrated in numerous ways. A systematic approach based on the Anderson quantum model of the Fermi gas in random lattices that can describe both diffusive and localized regimes has not yet been fully established. We build on a recent publication [V. Janiš, New J. Phys. 27, 073503 (2025)] and present a microscopic theory of disordered electrons that covers both the metallic phase with extended Bloch waves and the localized phase, where a propagating particle forms a quantum bound state with the hole left behind at the origin. The general theory provides a framework for constructing controlled approximations to one- and two-particle Green functions that satisfy the necessary conservation laws and causality requirements across the full range of disorder strength. It is used explicitly to derive a local, mean-field-like approximation for the two-particle irreducible vertices, enabling quantitative analysis of the solution's dynamic properties in both metallic and localized phases, including critical behavior at the mobility edge. A new instability line for the dynamical electron-hole correlation function of the metallic phase is introduced.

Many new families of quasicrystal-forming magnetic alloys have been synthesized and studied in recent years. For small changes of composition, the alloys can go from quasiperiodic to periodic (approximant crystals) while conserving most of the local atomic environments. Experiments show that many of the periodic approximants order at low temperatures, with clear signatures of ferromagnetic or antiferromagnetic transitions, and also in some cases undergo nonequilibrium spin glass transitions. In contrast, the quasicrystals are mostly found to be spin glasses. Systematically studying these alloys could help elucidate the role played by quasiperiodicity in (de)stabilizing long-range magnetic order. In this work, we study cluster spin models with the aim of understanding the mechanisms behind various types of long-range magnetic ordering in approximants and quasicrystals. These models embody key features of real systems, and to some extent are analytically tractable, both for periodic and quasiperiodic cases. For the quasicrystal, we describe two possible types of ordered magnetic phases in frustrated regions of the phase diagram. Our results should serve to motivate more detailed numerical explorations of such models so as to gain a better understanding of magnetic phases in quasicrystalline systems.

We investigate a hybrid device consisting of two quantum dots placed between a BCS superconductor and a semiconductor with a strong spin-orbit interaction. Assuming charge tunneling between quantum dots through spin-flip processes, we study the molecular Andreev bound states appearing in the proximized quantum dots. We show that the spin-orbit coupling splits a pair of the Andreev states into four in-gap quasiparticles. For the appropriate set of model parameters, two of these internal quasiparticle states merge, forming the zero-energy state. Under such circumstances, we obtain fully spin-polarized versions of the Majorana quasiparticles, localized on different quantum dots. This happens solely when the spin-orbit interaction is equally strong to the magnitude of crossed Andreev reflections, i.e., in the sweet spot. Otherwise, these processes are competitive, as can be observed in changes of the expectation values of the corresponding order parameters. We analyze signatures of such competition manifested under the nonequilibrium conditions for various configurations of the bias voltage. In particular, for the symmetric bias voltage between the normal electrodes and the Cooper pair splitter bias configuration, we reveal duality in the transport properties. Charge transport through the zero-energy state at the sweet spot is contributed by perfectly entangled crossed Andreev reflections with an (almost) ideal transmission. Transport studies would thus enable empirical detection of the molecular quasiparticle states and the efficiency of dissipation processes caused by the external normal electrodes.

Bosonization describes Fermi surface dynamics in terms of a collective field that lives on a part of phase space. While sensible semiclassically, the challenge of treating such a field quantum mechanically has prevented bosonization from providing as powerful a nonperturbative tool as in one dimension. We show that general Fermi surfaces can be exactly described by a particular $N\to \infty$ limit of a $U{\left(N\right)}_1$ Wess-Zumino-Witten model, with a tower of irrelevant corrections. This matrix-valued description encodes the noncommutative nature of phase space, and its (solvable) strongly coupled dynamics resolves the naive overcounting of degrees of freedom of the collective field without the need to cut the Fermi surface into patches. This approach furthermore provides a quantitative tool to study power-law corrections to Fermi surface dynamics.

The clock speed of topological quantum computers based on Majorana zero mode (MZM)-supporting nanoscale devices is limited by the time taken for electrons to traverse the device. We employ the time-dependent Landauer-Büttiker transport theory for current cross-lead correlations in a superconducting nanowire junction hosting MZMs. From the time-dependent quantum noise, we are able to extract traversal times for electrons crossing the system. After demonstrating a linear scaling of traversal times with nanowire length, we present a heuristic formula for the traversal times which accurately captures their behavior. We then connect our framework to a proposed experimental verification of this discriminant between spurious and genuine MZMs utilizing time-resolved transport measurements.

We develop a quantum kinetic theory of two-dimensional electron gases in which exchange is treated self-consistently at the Hartree-Fock level and enters as a nonlocal, momentum-dependent field in phase space. By starting from the Coulomb Hamiltonian, we derive a Hartree-Fock-Wigner equation for the electronic Wigner function and obtain a closed fluid model with exchange-corrected pressure, force, and current. For a single layer, we show that exchange renormalizes the Fermi velocity and can drive a long-wavelength plasmonic instability at low densities. In coupled layers, the same framework predicts acoustic-optical mode coupling and an instability forming long-lived charge-imbalance patterns that are not predicted by classical Vlasov and Boltzmann models. Finally, we apply the kinetic model to the Coulomb drag problem and show how exchange substantially enhances the drag resistivity in dilute GaAs double wells, quantitatively matching experimental observations.

We investigated the local magnetism of the organic conductor $\kappa \text{−}{\left(\mathrm{ET}\right)}_2\mathrm{Hg}{\left(\mathrm{SCN}\right)}_2\mathrm{Cl}$ with a quasitriangular lattice of weakly dimerized molecules through ${}^{13}\mathrm{C}$ nuclear magnetic resonance (NMR) spectroscopy. The NMR spectra and nuclear relaxation show that charge disproportionation occurs, associated with the metal-insulator transition at 31 K. The relaxation rate indicates that the paramagnetic spins in the insulating phase undergo a transition into a spin-singlet ground state with the emergence of orphan spins, a possible valence-bond-glass state. The present results are in high contrast to the spin-cluster paramagnetism of the electric dipole-liquid candidate $\kappa \text{−}{\left(\mathrm{ET}\right)}_2\mathrm{Hg}{\left(\mathrm{SCN}\right)}_2\mathrm{Br}$, having nearly identical material parameters. This fact indicates that these two systems are on the verge between distinct phases in both charge and spin degrees of freedom; a spin-singlet charge-ordered state versus a spin-active Mott insulating state, competing with each other on a triangular lattice of dimerized sites.

The coupling of magnons and plasmons offers a promising avenue for hybrid quantum systems, facilitating coherent energy and information transfer between magnetic and charge excitations. However, existing mechanisms often depend on spin-orbit coupling or temperature-activated processes, limiting their robustness for low-temperature quantum technologies. Here, we propose a coupling mechanism between plasmons and the two-magnon continuum in antiferromagnetic insulators, which operates at zero temperature and does not require spin-orbit coupling. Using a model system consisting of a two-dimensional electron gas on an insulating antiferromagnetic substrate, we show that the electric field of the plasmons interacts with the magnetically mediated electric polarization in the antiferromagnet, arising from bonds with broken inversion symmetry. This interaction enables a strong coupling to the spin-conserving two-magnon continuum, allowing for efficient hybridization and reaching the ultrastrong coupling regime.

We develop a theory of the nonlocal conductance $G_{RL}\left(V\right)$ for a disordered Majorana wire tuned near the topological transition critical point. Under these conditions, the antisymmetric part of the differential conductance, $[G_{RL}\left(V\right)-G_{RL}(-V)]/2$, is the dominant one for a sufficiently long wire. This reflects the charge-neutral nature of the critical modes in the wire. We factorize the conductance into a term describing propagation of the critical modes along the wire and terms describing the contacts between the wire and the normal leads. Topological transition affects only the former term. At the critical point, the localization length has a logarithmic singularity at the Fermi level, $l\left(E\right)\propto ln(1/E)$. This singularity directly manifests in the conductance magnitude as $ln|G_{RL}\left(V\right)/G_Q|\sim L/l\left(eV\right)$ for the wire of length $L\gg l\left(eV\right)$. Tuning the wire away from the immediate vicinity of the critical point changes the monotonicity of $l\left(E\right)$. This change in monotonicity allows us to define the width of the critical region around the transition point.

The intrinsic mechanisms of the magneto-optical Kerr signal in chiral superconductors often involve multiorbital degrees of freedom. Here, by considering a generic single-orbital and spinful Hamiltonian, we generalize the Onsager relation to obtain the necessary conditions for the optical anomalous Hall effect. Using the downfolding method, we identify two types of effective momentum-space magnetism responsible for the optical anomalous Hall conductivity arising from non-unitary and unitary pairing potentials respectively. The former is caused by the angular momentum of the Cooper pair, while the latter requires the participation of the spin-orbit coupling in the normal state and has been largely overlooked previously. Using concrete examples, we show that the unitary pairing can lead to both ferromagnetism and a complicated antiferromagnetic spin texture in the momentum space, resulting in an in-plane optical anomalous Hall effect with the magnetism parallel to the Hall-deflection plane. Our work reveals the essential role of the spin degree of freedom in the optical anomalous Hall effect.

Fracton codes have been intensively studied as novel topological states of matter, yet their fault-tolerant properties remain largely unexplored. Here, we investigate the optimal thresholds of self-dual fracton codes, in particular, the checkerboard code, against stochastic Pauli noise. By utilizing a statistical-mechanical mapping combined with large-scale parallel tempering Monte Carlo simulations, we calculate the optimal code-capacity threshold of the checkerboard code to be $p_{\text{th}}\simeq 0.107\left(3\right)$. This value is the highest among known three-dimensional codes and nearly saturates the theoretical limit for topological codes. Our results further validate the generalized entropy relation for two mutually dual models, $H\left(p_{\text{th}}\right)+H\left({\tilde{p}}_{\text{th}}\right)\approx 1$, and extend its applicability beyond standard topological codes. This verification indicates the Haah's code also possesses a code-capacity threshold near the theoretical limit $p_{\text{th}}\approx 0.11$. These findings highlight fracton codes as highly resilient quantum memory and demonstrate the utility of duality techniques in analyzing intricate error-correcting codes.

The bulk-edge correspondence principle, a cornerstone of topological physics, ensures that first-order topological systems host robust chiral edge states in two dimensions. This was later extended to higher-order phases, where second-order topological insulators exhibit localized, topologically protected corner states. While the transition between these distinct phases has been demonstrated in periodic systems, its existence in disordered platforms remains an open question. Here, we demonstrate a controllable topological phase transition between a second-order topological phase and a first-order topological phase in a two-dimensional photonic alloy. By tuning the magnetic doping concentration—implemented by attaching permanent magnets randomly to nonmagnetized yttrium iron garnet rods in an alternately magnetized honeycomb lattice with $C_3$ rotational symmetry—we flexibly control the system's topology. At zero doping, we observe higher-order corner states, confirmed by a trivial Chern number and nonzero bulk polarizations of $1/3$. As doping concentration increases, these corner states progressively merge with the bulk states, culminating in the closure of the bulk transmission gap. After the bulk transmission gap reopens with further increased doping, the system transitions to a first-order topological phase, characterized by a nontrivial Chern number of $-1$ and the emergence of a chiral edge state. This transition is reversible, providing a highly tunable and experimentally simple platform for flexibly switching between localized corner states and delocalized chiral edge states within a single photonic system.

Topological pumping manifests quantized particle transport protected by band topology in adiabatically driven systems. To date, all previous implementations relied on Abelian gauge fields; the role of non-Abelian gauge fields in tailoring spin-resolved topological transport remains relatively unexplored. Here, we uncover a pseudospin-sublattice-locked bidirectional topological pumping phenomenon mediated by U(2) non-Abelian synthetic gauge fields. By extending the three-site Aubry-André-Harper model to the non-Abelian regime with noncommuting hopping matrices, we engineer a one-dimensional U(2) lattice model that can decouple into two subspaces, where each one hosts hybridized pseudospin states at different sublattices, forming three quasiflat bands with nonzero Chern numbers. These bands resist full spin polarization, enforcing pseudospin-sublattice-resolved pumping dynamics: pseudospin pairs on few sublattices evolve with antiparallel phase relationships, while those on the remaining sublattices synchronize, locking pumping directionality to specific sublattice-pseudospin-locked configurations. Experimentally, we realize this mechanism through time-modulated non-Abelian topolectrical circuits, where dynamical equations preserve exact isomorphism with the theoretical lattice model. Direct measurements of voltage dynamics reveal pseudospin-sublattice-locked pumping trajectories. Our work establishes non-Abelian synthetic gauge fields as a versatile tool for pseudospin-resolved topological control, possessing potential applications in spin-sublattice-selective topological transport.