Quasicrystals are aperiodic solids with exotic physical properties. The mechanisms driving their growth are far from understood, particularly in the presence of rigid obstacles. Using in situ synchrotron x-ray tomography and molecular dynamics simulations, we investigate the interaction between decagonal quasicrystals and obstacles (shrinkage pores) during solidification of an ${\mathrm{Al}}_{79}{\mathrm{Co}}_6{\mathrm{Ni}}_{15}$ alloy. The results reveal defect-free quasicrystal growth around the pores, independent of pore size and geometry. Our findings point to a universal feature of aperiodic solids: their ability to accommodate structural disruptions due to additional (phasonic) degrees of freedom. This Letter opens new possibilities for synthesizing large-scale, single quasicrystals from a liquid metal precursor.

In devices based on two-dimensional electron gases (2DEGs), gate electrodes can be used to tune the electronic properties by controlling the electron density. Despite the prevalence of such gated systems, the properties of 2DEGs in these environments remain poorly understood quantitatively. To address this, we have studied the 2DEG in a dual-gate geometry using quantum Monte Carlo simulations alongside simpler approximate methods, and we have mapped out the phase diagram of the gated 2DEG as a function of electron density and gate distance. We find that the Wigner crystal is unstable at all densities when the gates are sufficiently close to the 2DEG, and we identify the critical gate distance at which the Wigner crystal phase appears. For larger gate separations, we determine the phase boundary for the reentrant crystal to liquid transition that occurs with decreasing density. Our Letter is particularly relevant to Wigner crystal phases recently observed in a variety of gated two-dimensional materials.

We realize a driven-dissipative Ising spin glass using cavity QED in a novel “4/7” multimode geometry. Gases of ultracold atoms trapped within the cavity by optical tweezers serve as effective spins. They are coupled via randomly signed, all-to-all Ising cavity-mediated interactions. Networks of up to $n=25$ spins are holographically imaged via cavity emission. The system is driven through a frustrated transverse-field Ising transition, and we show that the entropy of the spin glass states depends on the rate at which the transition is crossed. Despite being intrinsically nonequilibrium, the system exhibits phenomena associated with Parisi’s theory of equilibrium spin glasses, namely, replica symmetry breaking (RSB) and ultrametric structure. For system sizes up to $n=16$, we measure the Parisi function $q(x)$, Edwards-Anderson overlap $q_{\mathrm{EA}}$, and ultrametricity $K$ correlator; all indicate a deeply ordered spin glass under RSB. The system can serve as an associative memory and enable aging and rejuvenation studies in driven-dissipative spin glasses at the microscopic level.

Temporal correlations in pulsed electron beams reflect the microscopic dynamics of emission and interparticle interaction. In femtosecond electron emission from nanoscale field emitters, Coulomb interactions result in structured few-electron states with strong correlations in energy, time, and transverse momentum. Interactions with external fields may be used to both probe and further manipulate these correlated states. Here, we combine femtosecond-gated, event-based detection with inelastic electron-light scattering to directly map the photoelectron phase-space distribution of two-electron states. Our experiments demonstrate a bimodal structure in longitudinal phase space, with distinct contributions from interparticle interaction and dispersion. Moreover, we imprint a global phase modulation onto two-electron states and theoretically show that coherent shaping of few-electron phase-space distributions enables attosecond temporal correlations. This controlled phasing of few-electron states can be harnessed to produce tailored excitations and superradiance via two-electron energy postselection.

We investigate the secondary low-energy electron emission induced by inelastic electron scattering from graphene and layered materials thereof. By applying a coincidence detection of the primary scattered and the emitted secondary electron we unravel pronounced resonance features otherwise overshadowed by the largely structureless secondary electron energy distribution. Supported by density functional theory calculations we show that these structures are the signature of prominent resonances above the vacuum threshold which originate from interlayer states acting as a doorway state for electron emission. Remarkably, some of these doorway states open up only for samples with more than five layers.

High harmonic generation (HHG) in crystals could enable attosecond and ultraviolet light sources with high compactness, great controllability, and rich functions. However, the HHG process is accompanied by a quite large wave vector mismatch that is uncompensated by any traditional phase-matching method, directly limiting its energy conversion efficiency. Here, we propose an effective strategy for phase matching of HHG with arbitrary harmonic orders in crystals. Two flakes of twisted van der Waals crystals induce a nonlinear optical phase that depends on the crystal symmetry, twist angle, and harmonic order, which can be accurately designed to compensate for the phase mismatch in HHG. Guided by the twist-phase-matching theory, we achieved a record-high conversion efficiency of $\sim 4\times {10}^{-5}$ for the fifth HHG in twisted hexagonal boron nitride crystals within thickness of $\sim 1\mathrm{\mu }\mathrm{m}$. Moreover, the designed crystal has the polarization controllability that can emit a pure circularly polarized HHG light. Our Letter establishes a foundation for developing ultrashort-wavelength and ultrafast-pulse laser sources in compact solid-state tabletop systems for fundamental and applied sciences.

Conditional mutual information (CMI) is a widely studied multipartite correlation measure with a connection to the Markov property. Intriguingly, CMI can be generated by local dissipation, a phenomenon closely related to teleportation. The onset of long-range CMI corresponds to an information-theoretic mixed-state phase transition, with far-ranging implications for phase transitions, decoding, and state compressions. Little is known, however, about the conditions under which dissipation can generate long-range CMI. In this Letter, we provide the first rigorous results in this direction. We establish that CMI in high-temperature commuting Gibbs states subject to local dissipation decays exponentially under certain mild restrictions. Conversely, we show that the same setup can sustain long-range CMI at low temperatures. Our results establish the existence of finite-temperature information-theoretic phase transitions even in models that have no finite-temperature thermodynamic phase transitions.

Coherent spin-photon coupling is believed to play a significant role in silicon-based quantum computation. The resonant exchange (RX) qubit, formed in a triple quantum dot, is a promising platform for spin-photon coupling and qubit scaling due to the large electric dipole moment and full electrical control without auxiliary micromagnets. However, there has been no experimental demonstration of silicon RX qubits and their strong coupling to microwave photons to date. In this work, we report the strong coupling between an RX qubit and a high-impedance resonator on a Si/SiGe heterostructure with coupling strength $g_{\mathrm{s}}/(2\pi )=65.8\mathrm{MHz}$ and decoherence rate ${\gamma }_{\mathrm{s}}/(2\pi )=21.4\mathrm{MHz}$. Furthermore, the dependence of decoherence rate on detuning is measured and analyzed using a phenomenological model, indicating that the charge noise is the main source of decoherence. Our results demonstrate the viability of RX qubits in silicon, highlighting their crucial role of large-scale qubit integration for silicon quantum computation and opening new possibilities for quantum network.

${\text{Ta}}_2{\mathrm{NiSe}}_5$ undergoes a phase transition characterized by the opening of an energy gap and a reduction in its crystal symmetry below $T_c=326\mathrm{K}$. The primary cause of this transition is debated to be either electron-hole correlations, in line with the excitonic insulator hypothesis, or structural instability. The chain structure of ${\mathrm{Ta}}_2{\mathrm{NiSe}}_5$ enables effective control over its electronic and lattice properties by applying uniaxial strain. In this study, we utilize polarization-resolved Raman spectroscopy to demonstrate that the electronic and structural order parameters respond differently to uniaxial pressure applied along the Ta-Ni chains. Compressive strain reduces monoclinic distortions while enhancing excitonic fluctuations. Such disparate behavior suggests that many-body effects may significantly amplify exciton fluctuations even when monoclinic distortions are minimized, thereby supporting the excitonic nature of the phase transition.

Physical aging in polymers is a fundamental yet poorly understood phenomenon, as diverse macromolecular systems exhibit remarkably similar slow dynamics. Through molecular dynamics simulations of physically cross-linked networks composed of semiflexible polymers, we identify a previously unexplored class of self-similar aging. The network undergoes ultraslow coarsening characterized by a logarithmically growing mesh size, $L(t)\sim \ln t$, which governs the spatial organization, cohesive and bending energies, and the aging dynamics of the system. This single time-dependent length scale defines an internal clock, giving rise to spatiotemporal self-similarity of both structure and dynamics—offering a perspective on aging in soft and disordered materials.

We study the dynamical response of viscous materials to gravitational waves, in the context of a fully relativistic theory of fluid dynamics. For the first time, we calculate oscillation modes and scattering properties of viscous stars. Viscous stars absorb high-frequency radiation, following a dispersion relation introduced by Press. In the extremely large viscosity regime, stars would become reflectors of waves, but this regime appears to be forbidden by causality bounds. In the context of black hole mimickers, we show how maximally viscous stars on the threshold of stability mimic the absorption of a black hole with the same mass. Our results suggest that rotating viscous stars will amplify incoming radiation.

We present an experimental study of the flow regime and vortex structure in bulk polymeric turbulence through three-dimensional velocity measurements with unprecedented high spatial resolution. We demonstrate that, as the polymer concentration increases, the effect of polymers on the fluid energy dissipation rate can be categorized into two distinct regimes: the dissipation reduction regime and the maximum dissipation reduction (MDR) regime, and in the latter the effect of the polymers saturates. We reveal that the MDR regime occurs when the scale range affected by the polymer additives extends up to the integral length scale, rather than the generally accepted Lumley scale. This finding enables us to map out the phase diagram of the flow regimes of polymeric turbulence on the Reynolds number and Weissenberg number. Furthermore, we demonstrate that in the MDR regime, sheetlike vortex and strain structures dominate, which is traced to the fact that polymer stress stabilizes shear layers and reduces perturbation to shear instability. These results suggest that the MDR regime is a universal flow state in bulk polymeric turbulence and is the counterpart of the maximum drag reduction regime in wall-bounded flows. Our findings emphasize the significance of sheetlike vortex structures and offer new insights into predicting the critical conditions for the emergence of various flow regimes in viscoelastic fluids.

We present optical fiber experiments investigating the perturbed, nonintegrable evolution of soliton gases (SGs) under weak linear damping and gain. By measuring the amplitude and phase of the optical field in a recirculating loop, we determine the spectral distribution of SGs at various propagation distances. We demonstrate that a SG, initially prepared as a soliton condensate with a Weyl distribution, undergoes significant changes in its spectral distribution due to dissipation. Specifically, weak gain leads to the emergence of a bichromatic SG, while weak damping results in a SG with a semicircular spectral distribution at long propagation distances. These observed dissipation-driven changes in the SG’s spectral characteristics are not explained by existing hydrodynamic or kinetic theories.

Understanding the transparency of two-dimensional (2D) materials to intermolecular interactions—particularly their ability to transmit van der Waals (vdW) forces—is crucial for applications such as the design of 2D material-based nanofluidic and microelectromechanical systems. However, experimental studies have produced inconsistent and even contradictory conclusions regarding the vdW transparency of 2D materials. Here, we employ colloidal atomic force microscopy with a geometrically well-defined probe to measure pull-off and pull-in forces in a model system: graphene on silicon dioxide (${\mathrm{SiO}}_2$). Our results reveal that the total vdW force deviates significantly from the naive sum of contributions from graphene and its substrate. Intriguingly, the measured pull-off forces indicate that the effective surface energy of a suspended graphene monolayer can exceed that of its substrate-supported counterpart. Furthermore, our measurements of pull-in forces in substrate-supported systems suggest that graphene of 1–5 layers screens 15%–50% of the intrinsic solid-solid vdW interaction, consistent with Lifshitz theory calculations.

Two-dimensional (2D) van der Waals (vdW) magnetic semiconductors are a new class of quantum materials for studying the emergent physics of excitons and spins in the 2D limit. Twist engineering provides a powerful tool to manipulate the fundamental properties of 2D vdW materials. Here, we show that twist engineering of the anisotropic ferromagnetic monolayer semiconductor CrSBr leads to bilayer magnetic semiconductors with continuously tunable magnetic moment, dielectric anisotropy, exciton energy, and linear dichroism. We furthermore provide a model for exciton energy in the media with tunable anisotropy. These results advance fundamental studies of 2D vdW materials and open doors to applications to nano-optics, twistronics, and spintronics.

Although the search for quantum many-body phenomena in magnetic materials has a strong focus on highly frustrated systems, even unfrustrated quantum magnets show a multitude of unconventional phenomena in their spin excitation spectra. ${\text{YbBr}}_3$ is an excellent realization of the $S=1/2$ antiferromagnetic Heisenberg model on the honeycomb lattice, and we have performed detailed spectroscopic experiments with both unpolarized and polarized neutrons at all applied magnetic fields up to saturation. We observe extensive excitation continua, which cause strong renormalization and the decay of single magnons at higher fields, while coherent features include field-induced “shadows” of the single magnons and the spectacular emergence of a rotonlike excitation. To guide and interpret our experiments, we performed systematic calculations by the method of cylinder matrix-product states that provide quantitative agreement with the neutron scattering data and a qualitative benchmark for the spectral signatures of strong quantum fluctuations even in the absence of magnetic frustration.

Many magnetic materials are predicted to exhibit bosonic topological edge modes in their excitation spectra, because of the nontrivial topology of their magnon, triplon, or other quasiparticle band structures. However, there is a discrepancy between theory prediction and experimental observation, which suggests some underlying mechanism that intrinsically suppresses the expected experimental signatures, like the thermal Hall current. Many-body interactions that are not accounted for in the noninteracting quasiparticle picture are most often identified as the reason for the absence of the topological edge modes. Here we report persistent bosonic edge modes at the boundaries of a ladder quantum paramagnet with gapped triplon excitations in the presence of the full many-body interaction. We use tensor network methods to resolve topological edge modes in the time-dependent spin-spin correlations and the dynamical structure factor, which is directly accessible experimentally. We further show that signatures of these edge modes survive even when the noninteracting quasiparticle theory breaks down; we discuss the topological phase diagram of the model, demonstrate the fractionalization of its low-lying excitations, and propose potential material candidates.

The generation of pure spin currents is critical for low-dissipation spintronic applications, yet existing methods relying on spin-orbit coupling or ferromagnetic interfaces face challenges in material compatibility and operational robustness. We propose a paradigm-shifting approach to generate symmetry-protected pure spin currents by applying mechanical stress on insulating antiferromagnetic materials, i.e., the pure piezospintronic effect. We first classify magnetic point groups enabling pure piezospintronic effects. A novel first-principles method is developed to compute the spin dipole moments and coefficients of the piezospintronic effect. Integrating these methodologies with high-throughput screening, we identify FeOOH, ${\mathrm{Cr}}_2{\mathrm{O}}_3$, and NaMn$X$ ($X=\mathrm{As}$, Bi, P, Sb) with significant pure piezospintronic effects. Interestingly, we reveal that the ionic displacement contribution dominates the piezospintronic effect, in contrast to the piezoelectric effect. Our study not only provides a first-principles approach for investigating spin dipole moment related phenomena (e.g., ferrotoroidicity, fractional quantum spin dipole moment, piezospintronics), but also provides promising piezospintronic materials for experimental verification and industrial applications.

${\mathrm{F}}_1$-ATPase (${\mathrm{F}}_1$) is central to cellular energy transduction. Forcibly rotated by another motor ${\mathrm{F}}_{\mathrm{o}}$, ${\mathrm{F}}_1$ catalyzes adenosine triphosphate (ATP) synthesis by converting mechanical work into chemical free energy stored in the molecule ATP. The details of how ${\mathrm{F}}_{\mathrm{o}}$ drives ${\mathrm{F}}_1$ are not fully understood; however, evaluating efficient ways to rotate ${\mathrm{F}}_1$ could provide fruitful insights into this driving since there is a selective pressure to improve efficiency. Here, we show that rotating ${\mathrm{F}}_1$ with an angle clamp is significantly more efficient than a constant torque. Our experiments, combined with theory and simulation, indicate that the angle clamp significantly suppresses the nonequilibrium variation that contributes to the futile dissipation of input work.

On the surface of a vibrating liquid bath, instead of coalescing, a drop will continually bounce on a thin film of air between the drop and the free surface, giving rise to rich chaotic dynamics and quantum analog behavior. However, perpetual bouncing is yet to be demonstrated on a vibrating rigid solid, where the control of the drop’s motion is not limited by the bath dynamics. Here we show that vibration of an atomically smooth mica surface prolongs a drop’s hovering state by several orders of magnitude, increasing the time to wet from less than a second to several minutes. The excitation of the second spherical harmonic mode determines a transition between a bouncing state with high-amplitude rebounds, and a bound state, where the drop’s motion is locked onto the vibrating solid above a thin air layer. We further develop a coupled linear spring model, accounting for the drop’s deformation, that predicts bouncing trajectories without fitting parameters. Our results extend the scope of bouncing drop studies beyond the liquid bath and highlight the potential for precision manipulation of small liquid quantities in air.