An important route toward the preparation of cold molecules is magnetically tunable Feshbach resonances. Here we investigate an inelastic Feshbach resonance between a single pair of {}^{87}\mathrm{R}\mathrm{b} and {}^{39}\mathrm{K} atoms confined in an optical tweezer, with both atoms prepared in the |F=1,m_{\mathrm{F}}=-1⟩ state. By developing an in-situ imaging scheme for {}^{39}\mathrm{K}, we directly measure magnetic-field-dependent collisional loss without separating the atoms after the interaction. For weak confinement, the resonance position measured in our experiment differs from the bulk-gas experiments. In contrast, we observe a significant shift of the resonance toward higher magnetic fields as the tweezer trap depth increases. Coupled-channel calculations accounting for finite temperature effects fail to explain the magnitude of this shift, suggesting that it originates from differential optical responses of the open-channel atom pair and the weakly bound molecular state under strong confinement. Our results indicate that optical tweezer light can significantly modify Feshbach resonance properties, opening a pathway toward optical control of atom–atom interactions and weakly bound molecular states in dual-species tweezer platforms.

We report a comprehensive analysis of dynamics of two-dimensional vortex solitons with winding number S=1, maintained by a quadratic time-dependent potential with coefficient \kappa (t)={\kappa }_{\mathrm{d}\mathrm{c}}+{\kappa }_{\mathrm{a}\mathrm{c}}\cos \left(\omega t\right), which may periodically alternate between confinement and expulsion, in a combination with the self-focusing or defocusing cubic nonlinearity. Analytical results are reported for the linear version of the system, which is a nontrivial one too, while the nonlinear system is explored by means of systematic simulations. Fully stable axisymmetric vortex states in the system with the self-focusing nonlinearity are observed with scaled norm N taking values below a critical one, N_{\mathrm{c}\mathrm{r}}. In the interval of , we identify quasi-stable modes, which exhibit periodic splitting into a rotating pair of fragments and their recombination, thus breaking and restoring the axial symmetry. In the adjacent interval, , the system supports rotating robust states composed of two permanently separated fragments. There are no stable modes at N>N_{max}, where the vortices are destroyed by the collapse. In the case of the self-defocusing nonlinearity, the vortices remain stable for arbitrarily large values of the norm. These findings significantly enhance the understanding of the vortex dynamics in systems subject to the time-periodic “management”, which may be realized in atomic Bose−Einstein condensates and bulk optical waveguides.

Electronegativity is a cornerstone of chemical intuition, essential for rationalizing bonding, reactivity, and material properties. However, prevailing scales remain empirically derived, often relying on parameterized models or composite physical quantities. In this work, we introduce a universal electronegativity scale founded on the Atomic Mean Inner Potential (AMIP), also known as the average Coulomb potential, a fundamental, quantum-mechanical property accessible through both first-principles computation and electron-scattering experiments. Our scale, denoted {\chi }_{\mathrm{A}\mathrm{M}\mathrm{I}\mathrm{P},p}, is an analytic function of just three ground-state atomic descriptors and carries explicit physical units. It demonstrates excellent agreement with established scales and successfully classifies bonding types across 358 compounds, including adherence to the metalloid “Si rule”. Beyond replicating known trends, {\chi }_{\mathrm{A}\mathrm{M}\mathrm{I}\mathrm{P},1/2} proves to be a powerful predictive tool, accurately determining Lewis acid strengths for over 14 000 coordination environments (R^2=0.93) and \gamma-ray annihilation spectral widths for 36 elements (R^2=0.97), outperforming previous methods. By linking electronegativity directly to a measurable quantum property, this work provides a unified and predictive descriptor for electronic structure and chemical behavior across the periodic table.

We present a protocol for realizing parity detection of a bipartite system based on non-Hermitian spectral phase transition. The system comprises two superconducting qubits as information carriers and an auxiliary superconducting resonator. We derive a parity-dependent effective Hamiltonian, where the frequency of the resonator is shifted when the qubits are in even-parity states. The frequency shift results in a spectral phase transition in the non-Hermitian dynamical matrix in the Heisenberg picture, where the spectrum turns from purely imaginary to purely real. With a proper frequency shift, the spectral distinction between the even- and odd-parity cases leads to markedly different photon number dynamics, i.e., exponential growth for the odd-parity case, and bounded oscillations for the even-parity case. By measuring the photon number in the resonator after a fixed evolution time, the parity of the qubits can be reliably discriminated. Numerical simulations further demonstrate that the protocol is robust against systematic imperfections and decoherence, including the spontaneous emission and dephasing of the qubits, as well as cavity decay. These results establish a practical route to parity detection via non-Hermitian dynamics. This approach provides a scalable building block for superconducting-circuit quantum information processing.

Competing orders represent a central challenge in understanding strongly correlated systems. In this work, we employ projector quantum Monte Carlo simulations to study a sign-problem-free bilayer extended Hubbard model. In this model, a charge stripe phase, characterized by a peak at (0\pm 2\text{π}\delta ,0) is induced by highly anisotropic interlayer antiferromagnetic spin-exchange coupling J_z, and strongly suppressed by the decreasing spin-exchange anisotropy (i.e., introducing the spin-flip term J_{\mathrm{\perp }}); in contrast, the introduction of J_{\perp } favors the emergence of interlayer pairing superconductivity. We further demonstrate that the anisotropy of the interlayer spin-exchange directly governs the competition between these two phases, while the on-site interaction U plays a complex role in tuning both the charge stripe and superconductivity. Furthermore, against the background of charge stripes we discover the spin stripes, characterized by twice the period of charge stripes, indicating the profound internal connection between them. Our work identifies the key factors driving charge stripe formation, highlights the sensitivity of both the charge stripe and superconducting phases to interaction parameters, and thereby provides valuable insights into competing orders in strongly correlated systems.

Altermagnets constitute a recently identified magnetic phase that combines the absence of macroscopic magnetization, characteristic of antiferromagnets, with the spin splitting typically associated with ferromagnets. This hybrid nature enables stray-field-free spin transport and ultrafast spin dynamics, offering new opportunities for dissipationless spintronics and spin-caloritronics. Here, we perform a comprehensive symmetry analysis and advanced first-principles calculations to investigate the intrinsic spin Hall and spin Nernst effects in two-dimensional altermagnets, using bilayer MnPSe₃ as a representative example. In the nonrelativistic limit, interlayer sliding induces a d-wave-like spin splitting and generates time-reversal-odd, intraband-dominated spin Hall and spin Nernst responses. Changing the sliding direction alters the associated symmetry operations, thereby modifying the spin splitting of the Fermi surface and enabling tunable control of spin-transport properties. This modulation originates from symmetry-driven variations in the relative contributions of opposite spins. Our findings identify interlayer sliding as an effective route to tuning spin transport in altermagnets, establishing a versatile two-dimensional platform for exploring the interplay between altermagnetism and spin transport, and paving the way for future advances in altermagnetic spintronics and spin-caloritronics.

We investigate a frustrated four-spin plaquette spin-boson model with competing nearest-neighbor and diagonal Ising couplings, where each spin is coupled to an independent bosonic bath. Combining a path-integral strong-coupling analysis with variational matrix product state simulations, we obtain the ground-state phase diagram. In the strong-dissipation limit we map the model onto a classical plaquette and derive analytic phase boundaries between ferromagnetic, Néel, and stripe phases. At intermediate dissipation we find a delocalized phase and two localized ordered phases with Néel and stripe character. We show that the localized phases are separated by a first-order line, while each is connected to the delocalized regime via a continuous (second-order) localization transition, and that these three boundaries meet at a quantum triple point. Analysis of spin correlations and reduced density matrices further reveals that entanglement concentrates on nearest-neighbor (diagonal) bonds in the Néel (stripe) phase, whereas in the delocalized regime intra-plaquette two-spin entanglement is strongly suppressed in favor of enhanced spin-bath correlations.