We performed high-precision decay-pion spectroscopy of light $\mathrm{\Lambda }$ hypernuclei at the Mainz Microtron (MAMI) using the A1 spectrometer facility. By measuring the monochromatic ${\pi }^{-}$ momentum from the two-body weak decay ${}_{\mathrm{\Lambda }}{}^3\mathrm{H}\to {}^3\mathrm{He}+{\pi }^{-}$ and referencing it to the ${}_{\mathrm{\Lambda }}{}^4\mathrm{H}\to {}^4\mathrm{He}+{\pi }^{-}$ decay, we determined the $\mathrm{\Lambda }$ binding energy of ${}_{\mathrm{\Lambda }}{}^3\mathrm{H}$ with unprecedented accuracy. The obtained value, $B_{\mathrm{\Lambda }}{(}_{\mathrm{\Lambda }}^3\mathrm{H})=0.523\pm 0.013_{\mathrm{stat}}\pm 0.075_{\mathrm{syst}}.\mathrm{MeV}$, is consistent with the STAR result, but indicates a significantly deeper binding than inferred from earlier measurements. This result implies a stronger $\mathrm{\Lambda }$-deuteron interaction and provides stringent constraints on hyperon-nucleon interactions.

The lifetime of the $J^{\pi }=2^{+}$ state in the self-conjugate ${}^{88}\mathrm{Ru}$ nucleus has been determined in an experiment performed using rare-isotope beams provided by the new Facility for Rare Isotope Beams. This is the heaviest $N=Z$ nucleus for which such a measurement has been achieved. ${}^{88}\mathrm{Ru}$ was populated by both one-neutron knockout and charge-exchange reactions, and the lifetime of ${14.3}_{-3.4}^{+2.5}\mathrm{ps}$ was determined using the triple-foil plunger technique. The extracted electromagnetic transition strength shows that the quadrupole collectivity has dropped significantly compared with the highly deformed $N=Z$ region around $A\sim 80$. These results are compared with state-of-the-art large-scale shell-model and discrete nonorthogonal shell-model calculations. The theoretical calculations indicate a moderate triaxial deformation and suggest that low-lying states in this nucleus are no longer dominated by strong many-particle many-hole excitations, unlike the lighter, highly deformed $N=Z$ nuclei nearby.

Dodecagonal oxide quasicrystals (OQCs) have so far been limited to a few elemental systems, with no general formation mechanism established. Here, we demonstrate a versatile approach to OQC formation via a host-atom-induced transformation of a metal-oxide honeycomb network. Adsorption of Ba, Sr, or Eu onto the honeycomb layer triggers its reorganization into a dodecagonal tiling, as revealed by low-energy electron diffraction and scanning tunneling microscopy. Full conversion occurs when 73% of the honeycomb rings are occupied. Kelvin probe and UV photoelectron spectroscopy show a linear decrease in work function with increasing host coverage, followed by a sharp increase upon quasicrystal formation due to reduced host dipoles. This transformation mechanism enables the fabrication of structurally precise OQCs, including a new Eu-Ti-O phase that extends the field to lanthanide quasicrystals, forming a 2D grid of localized magnetic moments. The method might offer a more general route to explore lattice-matched substrates for epitaxial growth and may be adapted to other 2D honeycomb materials such as graphene, hexagonal ice, and silica, paving the way for engineered aperiodic systems beyond transition metal oxides.

We report the existence of algebraically localized eigenstates embedded within the continuum spectrum of 2D non-Hermitian systems with a single impurity. These modes, which we term algebraic states in continuum (AICs), decay algebraically as $1/|r|$ from the impurity site, and their energies lie within the bulk continuum spectrum under periodic boundary conditions. We analytically derive the threshold condition for the impurity strength required to generate such states. Remarkably, AICs are forbidden in Hermitian systems and in 1D non-Hermitian systems, making them unique to non-Hermitian systems in two and higher dimensions. To detect AICs, we introduce a local density of states as an experimental observable, which is readily accessible in photonic and acoustic platforms.

Both the minimal size of optically switched magnetic bits and the wavelengths of optically excited spin waves in optomagnonic devices are fundamentally diffraction limited. Here, we propose and experimentally demonstrate a novel method to overcome these limitations by using a specially designed magnetophotonic waveguide structure. This structure enables the creation of a sign-changing profile of the inverse Faraday effect (IFE) induced in the magnetic film by the circularly polarized femtosecond laser pulse tuned to the resonance of the optical TE guided mode. The spatial period of the IFE profile is subdiffractive, which allows for the launch of narrow band exchange-dominated magnetostatic spin waves. As experimentally demonstrated, their wavelengths are around 300 nm, and they can potentially be reduced to 100 nm. This opens new horizons for optomagnetic applications, ranging from logic elements to data processing devices.

It is always expected that tunneling coupling splits the energy of the eigenstates in proportion to its magnitude. This is also true for bound states in the continuum (BICs) in the waveguide strongly coupled to a Fabry-Pérot resonator. However, in the case of weak coupling, giant enhancement of the splitting takes place. Within the tight-binding model, we show that, in the limit of a weak coupling, the BIC formation conditions take a universal form independent of the particular structure of the periodic perturbations. Moreover, BIC energies become almost uniformly distributed over the energy band of the waveguide in agreement with the Erdős-Turán theorem. Analytical conclusions are supported by numerical calculations of two-dimensional waveguides with finite periodic modulation for both quantum-mechanical and optical cases. The results present a new approach to BIC construction and may pave the way towards quantum design of large-scale integrated systems of giant atoms with spatially distributed coupling to waveguides.

Random quantum states have various applications in quantum information science. We discover a new ensemble of quantum states that serve as an $\epsilon$-approximate state $t$-design while possessing extremely low entanglement, magic, and coherence. These resources can reach their theoretical lower bounds, $\mathrm{\Omega }(\log (t/\epsilon ))$, which are also proven in this Letter. This implies that, for fixed $t$ and $\epsilon$, entanglement, magic, and coherence do not scale with the system size, i.e., $O(1)$ with respect to the total number of qubits $n$. Moreover, we explicitly construct an ancilla-free shallow quantum circuit for generating such states by transforming $k$-qubit approximate state designs into $n$-qubit ones without increasing the support size. The depth of such a quantum circuit, $O(t[\log t{]}^3\log n\log [1/\epsilon ])$, is the most efficient among existing algorithms without ancilla qubits. A class of quantum circuits proposed in our Letter offers reduced cost for classical simulation of random quantum states, leading to potential applications in quantum information processing. As a concrete example, we propose classical shadow tomography using an estimator with superpositions between only two states, from which almost all quantum states can be efficiently certified by requiring only $O(1)$ measurements and classical postprocessing time.

Three-body forces, a type of nonperturbative strong interactions, are widely studied in nuclear physics. However, whether their inclusion is necessary in nuclear systems remains a topic of intense debate. In this Letter, we propose that the existence of three-body forces in certain three-body hadronic systems with definite $C$ parity is certain. Such systems consist of two components whose interactions are mediated by three-body forces—a mechanism not easily realized in conventional three-nucleon systems. We investigate two specific three-body hadronic systems, ${\overline{D}}_{s}DK$ and ${\overline{D}}^{*}D\eta$, using contact-range potentials. The two-body hadron-hadron interactions are constrained by reproducing their scattering lengths, while the three-body couplings are constrained by charge symmetry. Our results indicate that three-body forces play a minor role in binding the $I(J^{PC})=0(0^{--}){\overline{D}}_{s}DK$ system, but a crucial one in binding the $I(J^{PC})=0(1^{-+}){\overline{D}}^{*}D\eta$ system. In fact, three-body forces determine whether ${\overline{D}}^{*}D\eta$ forms a bound state, making this system a promising candidate for exploring three-body forces in hadronic physics.

Metastable atomic qubits are a highly promising platform for the realization of quantum computers, owing to their scalability and the possibility of converting leakage errors to erasure errors midcircuit. Here, we demonstrate and characterize a high-fidelity quantum gate set for the metastable fine-structure qubit encoded between the ${}^3{\mathrm{P}}_0$ and ${}^3{\mathrm{P}}_2$ states in bosonic strontium-88. We find single-qubit gate fidelities of 0.993(1), and two-qubit gate fidelities of 0.9945(6) after correcting for losses during the gate operation. Furthermore, we present a novel state-resolved detection scheme for the two fine-structure states that enables high-fidelity detection of qubit loss. Finally, we leverage the existence of a stable ground state outside the qubit subspace to perform midcircuit erasure conversion using fast destructive imaging. Our results establish the strontium fine-structure qubit as a promising candidate for near-term error-corrected quantum computers, offering unique scaling perspectives.

Achieving parametric excitation in an oscillating physical system involves periodically adjusting one of its parameters to modulate the oscillator’s natural frequency. This phenomenon has been observed in numerous systems within physics and engineering, profoundly transforming modern science and technology. Despite rapid progress, the parametric control of collective excitations, such as phonons, remains a challenge while promising to generate novel and intriguing effects in a largely unexplored field. Here, we investigate the terahertz (THz) field-induced dynamics of Raman-active phonons in the perovskite structure of ${\mathrm{LaAlO}}_3$. Utilizing intense THz pulses, we demonstrate a novel mechanism of parametric phonon excitation marked by substantial subharmonic components. Theoretical analysis can successfully capture the hallmarks of the observed phenomena in a physical scenario with the THz field inducing a parametric coupling between the Raman mode and pairs of acoustic phonon excitations.

Laser cooling of atomic motion enables advances in quantum information and precision metrology. However, the spatial spreading of subrecoil-laser-cooled atoms—crucial for understanding cooling mechanisms and atomic confinement—remains largely unexplored. Here, we analyze anomalous diffusion in subrecoil-laser-cooled atoms, where a velocity-dependent fluorescence rate $R(v)\propto |v{|}^{\alpha }$ governs transport properties. By tuning $\alpha$, we uncover transitions between normal, subdiffusive, and superdiffusive regimes. Notably, at $\alpha =3/2$, diffusion is minimized, leading to optimal atomic confinement. We further identify a conceptual link between subrecoil laser cooling and the Pomeau-Manneville map from nonlinear dynamics, revealing that anomalous diffusion can generically exhibit a nontrivial minimum in spatial spreading—even across seemingly unrelated physical systems.

We study theoretically the closure of a wound in a layer of epithelial cells in a living tissue after damage. Our analysis is informed by our recent experiments observing reepithelialization in vivo of Drosophila pupae. On time and length scales such that the evolution of the epithelial tissue near the wound is well captured by that of a 2D active fluid with local nematic order, we consider the free-surface problem of a hole in a bounded region of tissue, and study the role that active stresses in the surrounding tissue play in the closure of the hole. For parallel anchored nematic order at the wound boundary (as we observe in our experiments), we find that closure is accelerated by contractile active stresses and is slowed down when the stresses are extensile. Parallel anchoring also leads to the appearance of topological defects that annihilate upon wound closure.

The mean pairwise velocity of massive halos reflects the gravitational force law on cosmic scales. We combine cosmic microwave background intensity maps from the Atacama Cosmology Telescope and a galaxy catalog from the Sloan Digital Sky Survey to estimate the mean pairwise velocity using the kinematic Sunyaev-Zeldovich (kSZ) effect. On scales from 30 to 230 megaparsecs, we constrain the gravitational acceleration between pairs of halos at separation $r$ to be $g\propto 1/r^n$ with $n=2.1\pm 0.3$, which is consistent with Newtonian gravity in an expanding spacetime (i.e., the standard $\mathrm{\Lambda }\mathrm{CDM}$ model). This constraint shows agreement with an inverse quadratic radial dependence over the large distances separating galaxy halos, as expected in standard cosmology. Upcoming surveys have the potential to rule out $n=1$ at $10\sigma$ significance. Our results establish the kSZ effect as a powerful tool for testing gravity on cosmological scales.

We present strong-field photoelectron holography measurements of hydrogen chloride (HCl) that resolve subcycle dynamics in two ionization channels associated with the HOMO and HOMO-1 orbitals. The holograms in the photoelectron momentum distributions show different cutoffs and interference fringes tied to orbital-specific ionization potentials. Furthermore, molecular-frame photoelectron holograms from oriented HCl exhibit pronounced asymmetries that arise from the interplay of the molecular dipole and the ionic Coulomb field. These findings establish strong-field photoelectron holography as a sensitive probe of subcycle electron wave packet dynamics in polar molecules.

Dynamical control of quantum matter is a challenging, yet promising direction for probing strongly correlated states. Motivated by recent experiments in twisted ${\mathrm{MoTe}}_2$ that demonstrated optical control of magnetization, we propose a protocol for probing magnetization dynamics in flat-band ferromagnets. We investigate the nucleation and dynamical growth of magnetic bubbles prepared on top of a false vaccum in both itinerant ferromagnets and spin-polarized Chern insulators. For ferromagnetic metals, we emphasize the crucial role of a nontrivial quantum geometry in the magnetization dynamics, which in turn also provides a probe for the quantum metric. Furthermore, for quantum Hall ferromagnets, we show how properties of chiral edge modes localized at domain-wall boundaries can be dynamically accessed. Our Letter demonstrates the potential for nonequilibrium protocols to control and probe strongly correlated phases, with particular relevance for twisted ${\mathrm{MoTe}}_2$ and graphene-based flat-band ferromagnets.

We derive detailed and intergral fluctuation relations as well as a thermodynamic uncertainty relation constraining the exchange statistics of an arbitrary number of noncommuting conserved quantities among two quantum systems in transport setups arbitrary far from equilibrium. These universal relations, valid without the need of any efficacy parameter, extend the well-known heat exchange fluctuation theorems for energy and particle transport to the case of non-Abelian quantum transport, where the noncommutativity of the charges allows going beyond standard thermodynamic behavior. In particular, we show that this can lead to enhanced precision in the current fluctuations, and it allows for the inversion of all currents against their affinity biases.

Computing excitation spectra of quantum many-body systems is a promising avenue to demonstrate the practical utility of current noisy quantum devices, especially as we move toward the “megaquop” regime. For this task, here we introduce a tangent space excitation ansatz for quantum circuits, motivated by the quasiparticle picture of many-body systems and the structural similarity between quantum circuits and tensor networks. Increasing circuit depth by one layer to construct tangent space around the variational optimum of a parametrized quantum circuit, we show that massive low-energy single-particle states can be captured. Our ansatz relies on a distinct mechanism from that of the excitation ansatz in a matrix product state and projected entangled-pair state, and avoids intrinsic limitations of the latter. Comparing our approach with existing quantum excited-state algorithms, we find that with similar computational cost, both the number of excited states and accuracy are significantly improved. We demonstrate our ansatz in both one and two dimensions, and further show that this approach, implementable using the Hadamard test, is scalable and suitable for current quantum processors.