Global analysis of collider and fixed-target experimental data and calculations from lattice quantum chromodynamics (QCD) are used to gain complementary information on the structure of hadrons. We propose novel “window observables” that allow for higher precision cross-validation between the different approaches, a critical step for studies that wish to combine the datasets. Global analyses are limited by the kinematic regions accessible to experiment, particularly in a range of Bjorken-$x$, and lattice QCD calculations also have limitations requiring extrapolations to obtain the parton distributions. We provide two different window observables that can be defined within a region of $x$ where extrapolations and interpolations in global analyses remain reliable and where lattice QCD results retain sensitivity and precision.

We demonstrate nuclear magnetic resonance of optically trapped ground-state ultracold ${}^{87}\mathrm{Sr}$ atoms. Using a scheme in which a cloud of ultracold ${}^{87}\mathrm{Rb}$ is co-trapped nearby, we improve the determination of the nuclear $g$ factor, $g_I$, of atomic ${}^{87}\mathrm{Sr}$ by more than two orders of magnitude, reaching accuracy at the parts-per-million level. We achieve similar accuracy in the ratio of relevant $g$ factors between Rb and Sr. This establishes ultracold ${}^{87}\mathrm{Sr}$ as an excellent linear in-vacuum magnetometer. More generally, our Letter demonstrates how ultracold neutral atoms can be used for the precise determination of highly relevant atomic and nuclear magnetic properties. These results are important for ongoing efforts toward quantum simulation, quantum computation and optical atomic clocks employing ${}^{87}\mathrm{Sr}$, and other neutral alkaline-earth and alkaline-earth-like atoms.

Ice grains formed in a cryogenically cooled plasma exhibit fractal morphologies that drive distinct collective dynamics. By measuring and quantifying the dynamics of these grains in a plasma afterglow, we observe a new fundamental dynamical regime induced by fractal scalings of ice mass and collisional cross section. In this regime, grains become more coupled to flows of gas and ions as they get larger, while the influence of gravity remains comparatively small, even as the grains reach millimeter sizes. These dynamics are unattainable by compact spheres, and thus inaccessible to dusty plasma models that assume spherical grains, challenging models for systems ranging from laboratory nanoparticle synthesis to astrophysical dust transport.

We propose a fully ab initio approach to predicting thermal attenuation in elastic helium atom scattering amplitudes, validated through strong agreement with experiments on Nb(100) and $(3\times 1)\text{−}\mathrm{O}/\mathrm{Nb}(100)$ surfaces. Our results reveal the relative contributions from bulk, resonant, and surface phonon modes, as well as from different surface mode polarizations, providing insights into differences between smooth and corrugated surfaces. These findings advance understanding of surface dynamics and electron-phonon coupling, laying groundwork for future studies on surface superconductivity.

Nonreciprocal transport (current rectification) in bulk materials is rarer and more complex than at interfaces. We theoretically demonstrate ion current rectification in binary superlattices of oppositely charged nanoparticles and show that this effect strongly depends on the direction of the applied electric field. We derive an equation that relates the symmetry elements of the superlattice to the directions where rectification is forbidden. This equation is used to analyze the conductivity of different superlattices obtained from the numerical solution of the Poisson-Nernst-Planck equations.

We introduce a general first-principles methodology for computing electronic structure in a finite uniform magnetic field that allows for an arbitrary rational magnetic flux and nonlocal pseudopotentials at a comparable time complexity to conventional plane-wave pseudopotential approaches in zero-field conditions. The versatility of this method is demonstrated through comprehensive applications to both molecular and crystalline systems, including calculations of magnetizabilities, magnetically induced currents, and magnetic energy bands. Furthermore, we provide rigorous proofs of two properties for crystals in uniform magnetic fields: the “strong translational symmetry” and “magnetic band shift” phenomena.

All-electrical baseband control of qubits facilitates scaling up quantum processors by removing issues of crosstalk and heat generation. In semiconductor quantum dots, this is enabled by multispin qubit encodings, such as the exchange-only qubit. However, their performance is limited by unavoidable leakage states that are energetically close to the computational subspace. In this Letter, we introduce an alternative, scalable spin qubit architecture that leverages strong spin-orbit interactions of hole nanostructures for baseband qubit operations while completely eliminating leakage channels and reducing the overall gate overhead. This encoding is intrinsically robust to local variability in hole spin properties and operates with two degenerate states, removing the need for precise calibration and mitigating heat generation from fast signal sources. Finally, our architecture is fully compatible with current technology, utilizing the same initialization, readout, and multiqubit protocols of state-of-the-art spin-$1/2$ systems. By addressing critical scalability challenges, our design offers a robust and scalable pathway for semiconductor spin qubit technologies.

A new class of exact spacetimes in Einstein’s gravity, which are Kerr black holes immersed in an external uniform magnetic (or electric) field that is oriented along the rotational axis, is presented. These are axisymmetric stationary solutions to the Einstein-Maxwell equations such that (unlike in the Plebański-Demiański spacetime) the null directions of the Faraday tensor are not aligned with either of the two principal null directions of the Weyl tensor of algebraic type D (unlike the Kerr-Melvin spacetime). Three physical parameters are the black hole mass $m$, its rotation $a$, and the external field value $B$. For vanishing $B$ the metric directly reduces to standard Boyer-Lindquist form of the Kerr black hole, while for zero $m$ we recover a conformally flat Bertotti-Robinson universe with a uniform Maxwell field. For zero $a$, the spacetime is contained in the Van den Bergh–Carminati solutions which can be understood as the Schwarzschild black hole in a magnetic field. Our family of black holes with nonaligned Maxwell hair—that can be called the Kerr-Bertotti-Robinson black holes—may find application in various studies ranging from mathematical relativity to relativistic astrophysics.

Layered 2D van der Waals materials, such as transition metal dichalcogenides, are promising for nanoscale spintronic and optoelectronic applications. Harnessing their full potential requires understanding both intrinsic transport and the dynamics of optically excited spin and charge carriers, particularly the transition between excited spin polarization and the conduction band’s intrinsic spin texture. Here, we investigate the spin polarization of the conduction bands of bulk ${\mathrm{WSe}}_2$ using static and time-resolved spin-resolved photoemission spectroscopy, complemented by photocurrent calculations. Electron doping reveals the intrinsic spin polarization, while time-resolved measurements trace the evolution of excited spin carriers. We find that intervalley scattering is spin-conserving, with spin transport initially governed by photoexcited carriers and aligning with the intrinsic conduction band spin polarization after $\sim 150\mathrm{fs}$.

The dynamic coupling of a vibrating molecular bond to its responsive liquid environment can be described by non-Markovian friction in the framework of the generalized Langevin equation (GLE) and gives rise to line shifts as well as homogeneous and inhomogeneous spectral line broadening. By perturbation theory, we investigate how the interplay of nonharmonic bond-potential contributions and non-Markovian friction determines vibrational line shapes and positions. The accuracy of our perturbation theory is checked by simulations of the GLE. Based on bond potentials and time-dependent friction functions extracted from ab initio molecular dynamics simulations, our analytic theory traces the inhomogeneous line broadening of the infrared OH-stretch band of liquid water back to the coupling of non-Markovian friction to cubic and quartic bond-potential contributions.

Primordial black holes (PBHs) are hypothetical black holes with a wide range of masses that formed in the early Universe. As a result, they may play an important cosmological role and provide a unique probe of the early Universe. A PBH with an initial mass of approximately ${10}^{15}\mathrm{g}$ is expected to explode today in a final burst of Hawking radiation. In this Letter, we conduct an all-sky search for individual PBH burst events using the data collected from March 2021 to July 2024 by the Water Cherenkov Detector Array of the Large High Altitude Air Shower Observatory (LHAASO). Three PBH burst durations, 10, 20, and 100 s, are searched in the gamma-ray energy range from about 1 to 15 TeV, with no significant PBH bursts observed. The upper limit on the local PBH burst rate density is set to be as low as $181{\mathrm{pc}}^{-3}{\mathrm{yr}}^{-1}$ at 99% confidence level, representing the most stringent limit achieved to date.

Atomic imaging of molecules and intermolecular interactions is important for obtaining a deeper understanding of the related physics and chemistry. At a confined state in reticular matrix, molecular architecture can be stabilized for studying its static and dynamic behaviors, which is a milestone for molecular science but is still challenging in real space. Here, we use the coordination interactions between reticular building units of UiO-66 framework to maintain small molecules in a quasistatic structure. Low-dose electron microscopy is applied to resolving the atomic structures of these confined-state molecules. Meanwhile, the UiO-66 framework allows us modifying metal node structures for a controlled molecular manipulation by stretching and compressing. Then, the molecular statics and dynamics during stretching and compressing can be unraveled by directly measuring projected atomic positions, bond lengths, and peak widths via intensity profile analysis. These results perfectly support the predictions from our first-principles calculations, indicating the elastic deformation of coordination bonds and the varied vibration of ${\mathrm{C}}_6$ rings. This Letter not only represents an efficient strategy for atomically controlling and imaging the molecular statics and dynamics in reticular chemistry, but also opens up a new pathway for studying other molecular behaviors and interactions at confined states from new perspectives of atoms and bonds.

The photoelectric effect explained by Einstein is often regarded as a one-electron phenomenon, whereas the interaction of the escaping electron with other electrons, referred to as electron correlation, plays an important role in multielectron systems. In this Letter, we study the attosecond photoionization of the outer $s$ subshell of argon in its substantial minimum cross-section region formed by electron correlation, which was theoretically predicted in 1972 and experimentally confirmed using synchrotron radiation. Combining high-spectral resolution attosecond interferometry experiments and novel theoretical calculations allows us to identify the most essential electron correlations affecting the time of photoemission, solving the long-standing inconsistency between measurements and theories, and demonstrating the contribution of coherent couplings with shakeup channels. The measurement of time delays gives unprecedented insight into the photoionization process, unraveling details of the atomic potential experienced by the escaping electron and capturing its dynamics.

Quenched disorder can destroy magnetic order, for example, when a random field is applied in a two-dimensional Ising model. Even when an order exists in the presence of quenched disorder, it is usually only the survival of the order of the clean model. We present here a surprising phenomenon where an order emerges, driven by quenched disorder. This order has nothing in common with the order present in the clean model. This type of order by disorder differs from the usual thermal or quantum one. The classical $J_1-J_3$ Heisenberg model on the kagome lattice is studied by parallel tempering Monte Carlo simulations, with site dilution. After analyzing the effect of a few vacancies on the ground state, favoring noncoplanar configurations, we show the emergence of a low-temperature chiral phase and the progressive destruction of the collinear $q=4$ Potts order, the only order present in the absence of vacancies.

The jellium model is a paradigmatic problem in condensed matter physics, exhibiting a phase transition between metallic and Wigner crystal phases. However, its vanishing Berry curvature makes it ill suited for studying recent experimental platforms that combine strong interactions with nontrivial quantum geometry. These experiments inspired the anomalous Hall crystal (AHC)—a topological variant of the Wigner crystal. The AHC spontaneously breaks continuous translation symmetry but has a nonzero Chern number. In this Letter, we introduce $\lambda$-jellium, a minimal extension of the two-dimensional jellium model. Its Berry curvature distribution is controlled by a single parameter $\lambda$, where $\lambda =0$ corresponds to the standard jellium model. This setup facilitates the systematic exploration of Berry curvature’s impact on electron crystallization. The phase diagram of this model, established using self-consistent Hartree Fock calculations, reveals several interesting features: (i) The AHC phase occupies a large region of the phase diagram. (ii) Two distinct Wigner crystal phases, the latter enabled by quantum geometry, and two distinct Fermi liquid phases are present. (iii) A continuous phase transition separates the AHC and one of the Wigner crystal phases. (iv) In some parts of the AHC phase, the lattice geometry is nontriangular, unlike in the classical Wigner crystal. In addition to elucidating the physics of correlated electrons with nonzero Berry curvature, we expect that the simplicity of the model makes it an excellent starting point for more advanced numerical methods.