This Letter reports on the first evidence of inclusive Higgs-boson production at high transverse momentum in the $b\overline{b}$ final state, reconstructed in a single large-radius jet. The results are based on proton-proton collision data recorded by the ATLAS detector at the Large Hadron Collider at a center-of-mass energies of 13 and 13.6 TeV, corresponding to a total integrated luminosity of $301{\mathrm{fb}}^{-1}$. The study profits from the large background suppression provided by the use of a new transformer-based algorithm for jet identification and the sharper mass and transverse momentum, $p_{\mathrm{T}}$, resolution from a dedicated regression model. The yield relative to the standard model prediction for Higgs bosons produced at $p_{\mathrm{T}}$ larger than 450 GeV is measured to be $1.53\pm 0.2{7)}_{-0.27}^{+0.33}\pm 0.17$, where the first uncertainty is statistical, the second is experimental systematic, and the third accounts for theory systematic, corresponding to an observed (expected) significance of $3.8\sigma (2.5\sigma )$ relative to the background-only hypothesis. Results are also obtained in three Higgs boson $p_{\mathrm{T}}$ intervals and found to be compatible with standard model predictions, where the first uncertainty is statistical, the second is experimental systematic, and the third accounts for theory systematic.

The onset of nuclear effects in light-ion collisions is studied by measuring the ratio of $D^0$ meson production between NeNe and OO collisions at a center-of-mass energy per nucleon pair of 5.36 TeV recorded by the LHCb detector. The $D^0$ meson yields are measured differentially in transverse momentum ($p_{\mathrm{T}}$) for $0.5<p_{\mathrm{T}}<20\mathrm{GeV}$ in the rapidity ($y$) region $2.0<y<4.5$, and are normalized to the total number of recorded inelastic nucleus-nucleus collisions in each data sample. The resulting production ratio shows evidence of variation as a function of $p_{\mathrm{T}}$, which is inconsistent with predictions based on nuclear modification of nucleon structure alone. This measurement is consistent with the onset of quark-gluon plasma production with increasing nucleus size in high-energy nuclear collisions.

We use heavy-nucleus effective field theory to compute radiative corrections to two-neutrino double-$\beta$ decay ($2\nu \beta \beta$). Our main result is the first derivation of a universal radiative-correction factor for double-weak decays—the analog of the Sirlin function in single-$\beta$ decay—independent of nuclear matrix elements and excitation energies. This “double-weak Sirlin function” depends on the individual electron energies as well as their relative angle and differs significantly from the approximation obtained by summing two single-$\beta$ decay Sirlin functions. In addition, we calculate the nuclear-structure-dependent component of the radiative corrections and find that they can still be neglected at current experimental sensitivities. On the other hand, the double-weak Sirlin function induces distortions of the electron energies and angular spectra that are comparable in size to the leading nuclear-structure correction parametrized by the ratio of nuclear matrix elements, ${\xi }_{31}$. Our results indicate that extractions of nuclear-structure information and tests of the standard model from high-precision $2\nu \beta \beta$ measurements must include double-weak radiative corrections, implying that recent extractions of ${\xi }_{31}$ should be revisited.

We report a strong size dependence in the electronic heat capacity of silicon nanoclusters, tracing its origin to the distinctive electronic structure of surface atoms. By combining ab initio calculations with machine-learned local density of states and exploiting the extensivity of heat capacity, we develop a computational framework that resolves individual atomic contributions to the electronic heat capacity of silicon nanoparticles ranging from 1 to 100 nm. Deviating significantly from bulk behavior, atomic heat capacity increases by up to an order of magnitude for the undercoordinated surface atoms. Our analysis reveals that a surface layer approximately 3–4 Å thick—independent of structural order and cluster size—exhibits a distinct electronic density of states and dominates the electronic heat capacity as the cluster size decreases. The nonlinear temperature dependence is mainly governed by this surface layer. This work bridges the atomic-scale electronic structure with nanoscale thermal phenomena, resolving the microscopic mechanism behind a key thermodynamic property in silicon nanostructures. The future extension to the vibrational contribution and to other materials and surface states remains an open challenge for a comprehensive description of atom-scale thermal properties in nanostructures.

Electrical control of magnetism represents a fundamental route toward next-generation spintronic functionalities. In this Letter, we introduce a universal current-induced spin phenomenon in bilayer systems, termed the layer Edelstein effect (LEE), which serves as the natural counterpart of the layer Hall effect in real space. It is defined by the emergence of layer-resolved spin magnetizations with opposite components on the top and bottom layers, driven by an in-plane charge current and controllable by an external electric field. We establish the general existence of the LEE using a minimal bilayer $\mathit{k}·\mathit{p}$ theory. By combining symmetry analysis with a general bilayer stacking framework, we derive a model-independent symmetry criterion demonstrating that the LEE is generically allowed in a broad class of nonmagnetic bilayer stacking systems. We further show that the LEE admits two universal manifestations: explicit layer-opposite spin magnetization components mandated directly by symmetry, and components become activated upon symmetry reduction by external electric fields. First-principles calculations on stacked bilayer MoSSe, ${\mathrm{MoTe}}_2$, and ${\mathrm{WTe}}_2$ confirm the predicted effect and illustrate their experimental feasibility. Our Letter establishes the LEE as a generic symmetry-governed response of bilayer systems, providing a unified conceptual framework for electrically generating and manipulating layer-resolved spin polarization.

We study Gutzwiller-projected wave functions for triangular-lattice U(1) Dirac spin liquids in a Zeeman field, where we allow the U(1) gauge field to develop a gauge flux, resulting in (spin-split) spinon Landau levels. We find that at a given magnetization, the optimal candidate state has a finite flux chosen such that the spinon filling lies in a $|C|=1$ Landau-level gap: it gives the lowest variational energy and the smallest energy variance within our correlation-matrix reconstruction for local Heisenberg-type models. By symmetry, we argue that the finite gauge flux results in a nonzero (staggered) scalar spin chirality, as also numerically observed, and further find that the $|C|=1$ state exhibits dominant quasi-long-ranged 120° magnetic correlations. Studying the next-to-optimal wave function with a $|C|=2$ Landau-level gap, we observe unusual spin-nematic correlations. Our results may provide guidance for analyzing the magnetic-field response of Dirac spin liquid candidate materials and offer numerical diagnostics that can connect to the underlying theory of spinons coupled to an emergent U(1) gauge field.

The center of mass and helicity are two dynamic degrees of freedom of skyrmions. In this Letter, we study the current-driven skyrmion motion in frustrated $d$-wave altermagnets. Contrary to conventional wisdom, we find that the skyrmion helicity is not locked with the skyrmion Hall angle, but unidirectionally rotates with a global angular velocity proportional to the square of the current density. In addition, we find that the helicity rotation velocity is highly anisotropic, depending on the direction of current flows. We also observe helicity oscillation in the terahertz regime, where the nonlinear mixing between the fast and slow modes generates a comblike spectrum. Full atomistic spin dynamics simulations verify our theoretical predictions. Our results establish frustrated altermagnets as a promising platform for skyrmionics, terahertz technology, and magnon frequency comb.

Infrared (IR) and Raman vibrational spectra of materials and surfaces can be rather complex and are often interpreted in combination with simulations based on the double-harmonic approximation. A variety of anharmonic spectral features (band shifts, combination bands, overtones, hot bands, resonances) affect the spectra both quantitatively and qualitatively. We introduce a general method for the efficient description of these anharmonic features—including Fermi and Darling-Dennison resonances—in IR and Raman spectra of materials from first principles. Nuclear quantum effects are explicitly taken into account, and phonon couplings are treated nonperturbatively within a new subspace iterative vibrational configuration interaction (SI-VCI) approach. We apply the SI-VCI method to solid thiourea and solid ${\mathrm{CO}}_2$ (dry ice): two molecular crystals with distinct characteristics. Thiourea is a hydrogen-containing system for which we identify a strong three-mode Fermi-like resonance $SS:b+b^{\prime }$ between the fundamental of a symmetric stretching and the combination of two distinct bending modes of ${\mathrm{NH}}_2$ groups in the solid phase, which is not observed in the isolated gas-phase molecule. Our results, supported by group theoretical arguments, exclude the presence of bending overtones in the resonant mechanism. Dry ice exhibits four known resonances appearing in the form of dyads and triads (two in the IR spectrum and two in the Raman spectrum), which are also observed in the gas-phase isolated molecule. Our simulations predict an additional Fermi resonance in the IR spectrum of ${\mathrm{CO}}_2$ around $2000{\mathrm{cm}}^{-1}$ in the form of a dyad with a splitting $\delta \simeq 150{\mathrm{cm}}^{-1}$. We perform IR transmission experiments where the new resonant spectral feature is observed, assessing the predictiveness of the proposed theoretical approach.

We present a framework for mechanochemical self-organization in active solids where elasticity is reciprocally coupled to Hopf oscillators. Our model reveals a rich landscape of symmetry-protected phases identified through amplitude equations and group-theoretic analysis. We uncover a universal transition to compression-driven oscillation death, providing a physical basis for localized signaling dampening in biological tissues that resolves inconsistencies in previous models. Our work demonstrates that complex self-organization in active solids can be classified purely through symmetry arguments.

For centuries, the human distinction between consonant and dissonant dyadic sounds (“c-d perception phenomenon”) has remained an unresolved puzzle, igniting novel directions in physics research. Here, we demonstrate that nonlinear sound processing by the network of activated cochlear amplifiers reveals a close correlate of the psychoacoustic perception that matches the behavioral data to the level of the best phenomenological approach, suggesting that combination-tone avalanches triggered from coupled nonlinear oscillators, paired with biological information parsimony, may be the essential elements underlying this phenomenon. The observed correlate highlights the potential of a physics-driven explanation of behavioral phenomena that are commonly attributed to “the cortex” but may have their origins in the nonlinear properties of the involved sensors.

Bound states in the continuum (BICs) have been extensively exploited to enhance light-matter interactions in metamaterials, yet their emergence and utility in multiatom waveguide platforms remain far less explored. Here we study atom-waveguide-dressed BICs in a one-dimensional coupled-resonator waveguide, where two spatially separated atomic arrays couple to distinct resonators with time-dependent strengths. We show that these BICs host standing-wave photonic components and enable the transfer of unknown atomic quantum states encoded in the single-excitation subspace between the two arrays, with fidelities exceeding 99%. Going beyond traditional cascaded-quantum-network protocols, our scheme leverages BIC-assisted interference to remain robust against both disorder and intrinsic dissipation. Our results establish BICs as long-lived resources for high-fidelity quantum information processing in waveguide-QED architectures.

We demonstrate single-spin spectroscopy of a fluorescent tumbling defect in silicon called the “G center,” behaving as a pseudomolecule randomly reorienting itself in the crystalline matrix. Using high-resolution spin spectroscopy, we reveal a fine magnetic structure resulting from the spin principal axes jumping between discrete orientations in the crystal. Modeling the atomic reorientation of the defect shows that spin tumbling induces variations in the coupling to the microwave magnetic field, enabling position-dependent Rabi frequencies to be detected in coherent spin control experiments. By virtue of its pseudomolecule configuration, the G center in silicon is a unique quantum system to investigate the mutual interaction between optical, spin, and rotation properties in a highly versatile material.

Open systems feature a variety of phenomena that arise from non-Hermitian physics. Recent theoretical studies have offered many insights into these phenomena through the non-Bloch band theory, though many of the theory’s key features are experimentally elusive. In particular, the correspondence between complex momenta and non-Hermitian bands, while central to non-Bloch band theory, has so far defied direct experimental observation. Here we experimentally study the non-Hermitian spectral deformation in complex-momentum space, by implementing a non-Hermitian lattice with long-range couplings in the synthetic orbital-angular-momentum (OAM) dimension of photons inside a degenerate cavity. Encoding the complex momenta in the phase and amplitude modulations of the OAM modes, and devising a complex-momentum-resolved projective detection, we reconstruct the spectral deformation in complex-momentum space, where the eigenspectrum on the complex plane morphs through distinct geometries. This enables us to experimentally extract key information of the system under the non-Bloch band theory, including exceptional points in the complex-momentum space, the open-boundary spectra, and the generalized Brillouin zone. Our work demonstrates a versatile platform for exploring non-Hermitian physics and non-Bloch band theory, and opens the avenue for direct experimental investigation of non-Bloch features in the complex-momentum space.

Self-generated magnetic fields in laser-solid interactions are experimentally characterized to reveal the 3D location and local field strength, rather than path-integrated quantities, using multiview proton radiography and tomographic inversion. We infer magnetic fields that extend several millimeters off the target into the hot, rarefied corona, sufficient to strongly magnetize the plasma (${\mathrm{\Omega }}_e{\tau }_e\gg 1$). The data are compared to magnetohydrodynamic simulations incorporating recent improvements in modeling magnetic field generation and transport; the volume-averaged coronal field strength and magnetic flux agree to within 25% using a model with magnetic relocalization of transport, although the near-target morphology is not reproduced. This Letter demonstrates tomographic proton radiography as a valuable tool for investigating magnetic fields in laser-produced plasmas.

Geometric frustration lies at the heart of many unconventional quantum phases in strongly interacting electron systems. Here, we analytically determine the ground state magnetization of the half-filled Hubbard model on frustrated geometries where superstable states—eigenstates which are robust against frustration—are manifest. Our results apply to a broad class of lattices, including those where altermagnetic and superconducting states are known to emerge. Furthermore, they provide evidence for phase transitions involving a geometric rearrangement of magnetic correlations in the thermodynamic limit.