Many-body entanglement is an essential resource for many quantum technologies, but its scalable generation has been challenging on qubit platforms. However, the generation of continuous-variable (CV) entanglement can be extremely efficient, but its utility is rather limited. In this Letter, we propose a scheme to combine the best of both qubit and CV approaches: a systematic method to download useful many-qubit entanglement from the efficiently generated CV cluster states. Our protocol is based on one-bit teleportation of the qubit correlation encoded in the displaced Gottesman-Kitaev-Preskill basis. To characterize the practical performance of our scheme, we develop an equivalent circuit to map dominant CV errors to single-qubit preparation errors. Particularly, we relate finite squeezing error to qubit erasure, and show that only 5.4 dB squeezing is sufficient to implement robust qubit memory or quantum computation (QC), and 11.9 dB for fault-tolerant QC. Our protocol can be implemented with the operations that are common in many bosonic platforms.

We point out that the rotation angle $\beta$ of cosmic birefringence, which is a recently reported parity-violating signal in the cosmic microwave background (CMB), has a phase ambiguity of $n\pi (n\in \mathbb{Z})$. This ambiguity has a significant impact on the interpretation of the origin of cosmic birefringence. Assuming an axionlike particle (ALP) as the origin of cosmic birefringence, this ambiguity can be partly broken by the anisotropic cosmic birefringence and the shape of the CMB angular power spectra. We forecast constraints on $n$ from ongoing and upcoming experiments and find that most nonzero values of $n$ can be excluded using the cross-power spectrum between $E$ and $B$ modes. We also find that measuring the reionization bump in the $E$-mode auto-power spectrum can give further constraints, provided that the optical depth $\tau$ is determined independently of the CMB. The change in the low-$l$ $E$-mode power spectrum may also provide a potential solution to the tension in $\tau$ suggested by the latest CMB and baryon acoustic oscillation measurements.

We propose a new method to tomographically probe cosmic birefringence using radio galaxies. We show that the redshift evolution of the cosmic birefringence angle induced by a slow-rolling pseudoscalar field, which is a candidate for dynamical dark energy, is independent of the detailed model of the pseudoscalar field. This universal profile evolves predominantly at $z\lesssim 10$. In contrast, if the origin is a dark matter-like pseudoscalar field, the resulting birefringence angle tends to be negligible in the low-redshift regime. This new insight provides a strong motivation to independently test the cosmic birefringence using polarized astrophysical sources such as radio galaxies. We find that a sample size of $\mathcal{O}{10}^5–{10}^6$ is required to distinguish the profiles, which is within the scope of ongoing and upcoming radio surveys such as ASKAP or SKA.

In this study, we extend the application of the Lee-Yang phase transition theorem to the realm of anti–de Sitter (AdS) black hole thermodynamics, thereby deriving a comprehensive complex phase diagram for such systems. Our research augments extant studies on black hole thermodynamic phase diagrams, particularly in the regime above the critical point, by delineating the Widom line of AdS black holes. This boundary segregates the supercritical domain of the phase diagram into two disparate zones. As the system traverses the thermodynamic crossover within the supercritical region, it undergoes a transition from one supercritical phase to another, while maintaining the continuity of its thermodynamic state functions. This behavior is fundamentally different from that below the critical point, where crossing the coexistence line results in discontinuities of thermodynamic state functions. The Widom line enables a thermodynamic crossover between single-phase states without traversing the spinodal that emerges in the critical region.

Vortex or antivortex modes that carry orbital angular momentum (OAM) have provided a novel degree of freedom for modern optics and practical applications. However, their robust transport has thus far been limited to two-dimensional photonic systems. Here, we report on the first experimental observation of topological vortex and antivortex transport in a three-dimensional (3D) photonic metamaterial with a topological disclination defect. Using microwave near-field measurements, we directly observe topological vortex and antivortex modes bound to and propagated stably along a one-dimensional disclination line defect with preserved OAM in a 3D photonic disclination metamaterial. Moreover, we demonstrate that topological vortices and antivortices, which transport opposite OAMs, can be selectively excited with chiral sources and are robust against metallic obstacles and random disorders. Our Letter not only establishes an ideal platform for exploring topological lattice defects in 3D photonic systems but also opens a new avenue for designing OAM-based photonic devices.

Quantized conductance in quasi-one-dimensional systems not only provides a hallmark of ballistic transport, but also serves as a gateway for exploring quantum phenomena. Recently, a unique hidden Rashba effect, which arises from the compensation of opposite spin polarizations of a Rashba bilayer in inversion symmetric crystals with dipole fields, such as bismuth oxyselenide (${\mathrm{Bi}}_2{\mathrm{O}}_2\mathrm{Se}$), has attracted tremendous attention. However, investigating this effect utilizing conductance quantization remains challenging. Here we report the conductance quantization observed in a chemical vapor deposition (CVD)-grown high-mobility ${\mathrm{Bi}}_2{\mathrm{O}}_2\mathrm{Se}$ nanoribbon, where quantized conductance plateaus up to $44\times 2e^2/h$ ($e$ is the elementary charge, $h$ is the Planck’s constant, and the factor 2 results from spin degeneracy) are achieved at zero magnetic field. Because of the hidden Rashba effect, the quantized conductance remains in multiples of $2e^2/h$ without Zeeman splitting even under magnetic field up to 12 T. Moreover, within a specific range of magnetic field, the plateau sequence follows the Pascal triangle series, namely, $(1,3,6,10,15\dots )\times 2e^2/h$, reflecting the interplay of size quantization in the two transverse directions. These observations are well captured by an effective hidden Rashba bilayer model. Our results demonstrate ${\mathrm{Bi}}_2{\mathrm{O}}_2\mathrm{Se}$ as a compelling platform for spintronics and the investigation of emergent phenomena.

The (emergent) symmetry of a critical point constitutes fundamental pieces of information for determining the universality class and effective field theory. However, the underlying symmetry thus far can be conjectured only indirectly from the dimension of the order parameters in symmetry-breaking phases, and its correctness requires further verification to avoid overlooking hidden order parameters, which by itself is also a difficult task. In this Letter, we introduce an unbiased numerical approach to identify the underlying (emergent) symmetry of a critical point in quantum many-body systems without prior knowledge about the corresponding low-energy effective field theory. By numerically calculating the reduced density matrix in a very small subsystem of the total system, the Anderson tower of states in the entanglement spectrum can be obtained, clearly reflecting the underlying (emergent) symmetry of criticality. This is attributed to the fact that the entanglement spectrum can reveal the broken symmetry of the ground state of entanglement Hamiltonian after cooling from the critical point along an extra entanglement-temperature axis.

Recent works on the scaling behaviors of entanglement entropy at the $SO(5)$ deconfined quantum critical point (DQCP) sparked a huge controversy. Different bipartitions gave out totally different conclusions for whether the DQCP is consistent with a unitary conformal field theory. In this Letter, we connect two previously disconnected fields—the many-body entanglement and the surface criticality—to reveal the behaviors of entanglement entropy in various bipartite scenarios, and point out that only the ordinary bipartition purely reflects the criticality of the bulk; otherwise, the extra gapless edge mode will also contribute to the entanglement. We have demonstrated that the correspondence between the entanglement spectrum and the edge energy spectrum still approximately persists even at a bulk-gapless point, thereby influencing the behavior of entanglement entropy. Our results establish that boundary conditions induced by the cut are decisive for entanglement-based probes and provide practical protocols to separate bulk from boundary contributions.

Higher-form symmetry in a tensor product Hilbert space is always emergent: The symmetry generators become genuinely topological only when the Gauss law is energetically enforced at low energies. In this Letter, we present a general method for defining the ’t Hooft anomaly of higher-form symmetries in lattice models built on a tensor product Hilbert space. In $(2+1)\mathrm{D}$, for given Gauss-law operators realized by finite-depth circuits that generate a finite 1-form $G$ symmetry, we construct an index representing a cohomology class in $H^4(B^{2}G,U(1))$, which characterizes the corresponding ’t Hooft anomaly. This construction generalizes the Else-Nayak characterization of 0-form symmetry anomalies. More broadly, under the assumption of a specified formulation of the $p$-form $G$ symmetry action and Hilbert space structure in arbitrary $d$ spatial dimensions, we show how to characterize the ’t Hooft anomaly of the symmetry action by an index valued in $H^{d+2}(B^{p+1}G,U(1))$.

By sidestepping the intractable calculations of many-body wave functions, density functional theory has revolutionized the prediction of ground states of materials. However, predicting nonlinear responses—critical for next-generation quantum devices—still relies heavily on explicit wave functions, limiting computational efficiency. In this Letter, using the circular photogalvanic effect in Weyl semimetals as a representative example, we realize a 1000-fold computational speedup by eliminating the explicit dependence on wave functions. Our approach leverages the one-to-one correspondence between free parameters of Weyl fermions and the associated responses to obtain precise wave-function-free formulations. Applying our methodology, we systematically investigated known Weyl semimetals and revealed that ${\text{Ta}}_3{\mathrm{S}}_2$ exhibits photocurrents an order of magnitude greater than those observed in TaAs, with potential for an additional order-of-magnitude enhancement under strain. To further demonstrate the generality of our approach, we obtained a wave-function-free formula for the Berry-curvature dipole in Weyl semimetals. Our Letter paves the way for substantially more efficient screening and optimization of nonlinear electromagnetic properties in topological quantum materials.

Topological magnons offer unique opportunities for low-dissipation spin transport, but achieving nonvolatile control over their topological states remains a significant challenge. Here, using a Heisenberg-Dzyaloshinskii-Moriya model and symmetry analysis, we propose a ferroelectrically tunable magnonic platform that enables reversible switching among three distinct topological phases: a second-order topological magnon insulator, a topological magnon insulator, and a normal magnon insulator. This transition is characterized by the simultaneous emergence and reversal of spontaneous magnon valley polarization. We further identify the ${\mathrm{Ti}}_3{\mathrm{I}}_8$ monolayer with a breathing kagome lattice as a promising material platform that supports electric-field-driven topological switching and reversal of spontaneous magnon valley polarization, as confirmed by first-principles calculations. Notably, this material platform also hosts electrically controllable valley-dependent magnonic transport, including valley Hall and valley Nernst effects. This Letter establishes topological magnons as a functional bridge linking ferroelectricity with magnon cornertronic and magnon valleytronic responses.

Magnon torques, which can operate without involving moving electrons, could circumvent the Joule heating issue. In conventional magnon torque systems, the spin source layer with strong spin-orbit coupling is utilized to inject magnons, and the efficiency is limited by the inherent spin Hall conductivity of the spin source layer. In this Letter, we observe magnon torques in the Cr/NiO/ferromagnet heterostructure with the effective spin Hall conductivity of $2.45\times {10}^5\hslash /2e{\mathrm{\Omega }}^{-1}{\mathrm{m}}^{-1}$, twice that of the best conventional magnon torque system. We demonstrate the magnon-torque-driven switching of a perpendicularly magnetized CoFeB layer at room temperature, with a switching power consumption density of $0.136\mathrm{mW}\mathrm{\mu }{\mathrm{m}}^{-2}$. We find that the magnon torque originates from the orbital hybridization and interfacial inversion symmetry breaking at the Cr/NiO interface. Our findings not only significantly enhance the efficiency of magnon torques but also provide key insights into the fundamental mechanisms of magnon injections.

We study the optimal performance of an information engine consisting of an overdamped Brownian bead confined in a controllable, $d$-dimensional harmonic trap and additionally subjected to gravity. The trap’s center is updated dynamically via a feedback protocol designed such that no external work is done by the trap on the bead while maximizing the extraction of gravitational potential energy and achieving directed motion. We show that performance improves when thermal fluctuations in directions perpendicular to gravity are harnessed. This improvement arises from feedback cooling of these transverse degrees of freedom, along which all heat is extracted. Strikingly, engines based on a single transverse degree of freedom already outperform engines based solely on vertical ($z$) measurements. This engine design modularizes the functions of harnessing fluctuations and storing free energy, drawing a close analogy to the Szilard engine.

The evaporative decay of mixed heavy and light water clusters was measured. The branching ratios of the three isotopologue molecules scale with the deuterium fraction from cluster size $N=9$ and up, including across the well-known shell closing at $N=21$, and are consistent with macroscopic surface values. Differences in the free energies of competing channels derived from the scaled distributions take the simplest possible form of a single energy parameter and the deuterium-protium mixing entropy. The observations here represent a direct observation of the isotopic mixing entropy. The energy parameter is consistent with zero point vibrational energy differences of the free and condensed water molecule for both ${\mathrm{H}}_2\mathrm{O}/\mathrm{HDO}$ and $\mathrm{HDO}/{\mathrm{D}}_2\mathrm{O}$ ratios.

Mechanical qubits offer unique advantages over other qubit platforms, primarily in terms of coherence time and possibilities for enhanced sensing applications, but their potential is constrained by the inherently weak nonlinearities and small anharmonicity of nanomechanical resonators. We propose overcoming this shortcoming by using squeezed-Fock states of phonons in a parametrically driven nonlinear mechanical oscillator. We find that, under two-phonon driving, squeezed-Fock states become eigenstates of a Kerr-nonlinear mechanical oscillator, featuring an energy spectrum with exponentially enhanced and tunable anharmonicity, such that the transitions to higher energy states are exponentially suppressed. This enables us to encode the mechanical qubit within the ground and first excited squeezed-Fock states of the driven mechanical oscillator. This kind of mechanical qubit is termed mechanical squeezed-Fock qubit. We also show that our mechanical qubit can serve as a quantum sensor for weak forces, with its resulting sensitivity increased by at least one order of magnitude over that of traditional mechanical qubits. The proposed mechanical squeezed-Fock qubit provides a powerful quantum phonon platform for quantum sensing and information processing.

This Letter reports the first calculation of the gravitational form factors (GFFs) of the scalar glueball, performed via lattice field theory in Yang-Mills theory at a single lattice spacing. The glueball GFFs are compared with those of other hadrons as determined in previous lattice calculations, providing strong indications that glueballs have a different gluonic structure than typical hadronic states. A mass radius of 0.263(31) fm is predicted, supporting previous suggestions that the scalar glueball is significantly smaller than other hadrons.