强关联电子
We present a method to numerically obtain low-energy effective models based on a unitary transformation of the ground state. The algorithm finds a unitary circuit that transforms the ground state of the original model to a projected…
Following the successful prediction of the superconducting phase diagram for infinite-layer nickelates, here we calculate the superconducting $T_{\mathrm{c}}$ vs. the number of layers $n$ for finite-layer nickelates using the dynamical…
The recent discovery of ambient-pressure superconductivity in thin-film bilayer nickelates opens new possibilities for investigating electronic structures in this new class of high-transition temperature $T_C$ superconductors. Here, we…
Topological entanglement entropy (TEE) represents an intrinsic contribution to the entanglement entropy (EE) in topologically ordered systems. In quantum information theory, strong subadditivity (SSA) is a fundamental property of EE,…
Fractional Chern insulators (FCI) with crystalline symmetry possess topological invariants that fundamentally have no analog in continuum fractional quantum Hall (FQH) states. Here we demonstrate through numerical calculations on model wave…
Despite its many advantages, the sensible application of the Hybrid Monte Carlo (HMC) method is often hindered by the presence of large - or even infinite - potential barriers. These potential barriers partition the configuration space into…
Extending many-body numerical techniques which are powerful in the context of simple model calculations to the realm of realistic material simulations can be a challenging task. Realistic systems often involve multiple active orbitals,…
The layered honeycomb material BaCo$_2$(AsO$_4$)$_2$ (BCAO) is of topical interest because its magnetic state is related to that of the Kitaev magnet $\alpha$-RuCl$_3$. Using thermal transport to probe how magnetic excitations interact with…
We study the boundary criticality enriched by boundary fermions, which ubiquitously emerge in topological phases of matter, with a focus on topological insulators and topological superconductors. By employing dimensional regularization and…
Electronic liquid crystal (ELC) phases are spontaneous symmetry breaking states believed to arise from strong electron correlation in quantum materials such as cuprates and iron pnictides. Here, we report a direct observation of a smectic…
We use momentum-dependent electron energy-loss spectroscopy in transmission to study collective charge excitations in the layer metal Sr$_2$RuO$_4$. This metal has a transition from a perfect Fermi liquid below $T\approx30\,$K into a…
We develop an unrestricted Hartree-Fock mean-field method including Coulomb repulsion $U$, $V$ and spin-orbital coupling $\lambda$ self-consistently to investigate the mechanism of structural instability and magnetic ordering in…
Electronic systems with quadratic band touchings, commonly found in two- and three-dimensional materials such as Bernal-stacked bilayer graphene, kagome metals, HgTe, and pyrochlore iridates, have attracted significant interest concerning…
We investigate the non-equilibrium dynamics of a Heisenberg spin-1/2 chain driven by a periodic magnetic field. Based on its instantaneous integrability and inherent symmetry, we analytically study the magnetization and many-body tunneling…
The origin of charge transport and magnetization anisotropy was studied in DyB12, an antiferromagnetic (AF) metal with Neel temperature TN = 16.3 K that exhibits both cooperative Jahn-Teller distortions of the fcc crystal structure and…
We report a detailed high-field/high-frequency ferromagnetic resonance (HF-FMR) study of low-energy magnon excitations in the van der Waals ferromagnet Fe$_3$GeTe$_2$. At 2 K, the field dependence of the magnon branches is well described by…
Superconductivity in La$_{4}$Ni$_{3}$O$_{10}$ has been reported to emerge upon suppression of intertwined spin and charge density wave (SDW/CDW) order, suggesting a possible connection to the pairing mechanism. Here we report a systematic…
We present a comprehensive study of topological phases in the SO($n$) spin chains using a combination of analytical parton construction and numerical techniques. For even $n=2l$, we identify a novel SPT$^2$ phase characterized by two…
Within the confined phase of (2+1)D lattice gauge theories a roughening transition arises between a weakly confined regime with floppy string excitations and a strongly confined regime with stiff string excitations. In this work, we use an…
We investigate the S=1/2 antiferromagnetic Heisenberg model with a 3$\times$3 checkerboard lattice structure in a longitudinal magnetic field. By using the stochastic series expansion quantum Monte Carlo (SSE-QMC) method, we obtain the…