相关论文: Fluctuation driven topological Hund insulators

To describe the cuprate superconductors, models of strongly correlated electronic systems, such as the Hubbard or t-J models, are commonly employed. To study these models, projected (Hubbard) operators have to be used. Due to the…

We present a formalism for strongly correlated electrons systems which consists in a local approximation of the dynamical three-leg interaction vertex. This vertex is self-consistently computed with a quantum impurity model with dynamical…

Topological phases of electrons such as topological insulators and quantum Hall states typically require strong spin-orbit coupling or magnetic fields. In this study, we consider an electron system coupled to a spin system, where electrons…

We investigate the Hubbard model on the honeycomb lattice with intrinsic spin orbit interactions as a paradigm for two-dimensional topological band insulators in the presence of interactions. Applying a combination of Hartree-Fock theory,…

Driven by various physical origins, the interesting reentrant phenomena in quantum Hall effect (QHE), quantum anomalous Hall effect (QAHE) and non-Hermitian systems have been discussed recently. Here, we present that the reentrant phenomena…

Recent investigations suggest that both spin-orbit coupling and electron correlation play very crucial roles in the $5d$ transition metal oxides. By using the generalized Gutzwiller variational method and dynamical mean-field theory with…

We describe a new microscopic approach for analyzing interacting electron systems with local moments or, in principle, any local order parameter. We specialize attention to the doped Mott insulator phase of the Hubbard model, where standard…

The commensurate $p/q$-filled $n$-component Hubbard chain was investigated by bosonization and high-precision density-matrix renormalization-group analysis. It was found that depending on the relation between the number of components $n$,…

One of the most remarkable results of quantum mechanics is the fact that many-body quantum systems may exhibit phase transitions even at zero temperature. Quantum fluctuations, deeply rooted in Heisenberg's uncertainty principle, and not…

The interface between a topological insulator and a ferromagnetic insulator exhibits an interesting interplay of topological Dirac electrons and magnetism. As has been shown recently, the breaking of time-reversal invariance by magnetic…

Correlated electrons in a binary alloy $A_{x}B_{1-x}$ are investigated within the Hubbard model and dynamical mean--field theory (DMFT). The random energies $\epsilon_{i}$ have a bimodal probability distribution and an energy separation…

We present a comprehensive study of the spin excitations - as measured by the dynamical spin structure factor $S(q,\omega)$ - of the so-called block-magnetic state of low-dimensional orbital-selective Mott insulators. We realize this state…

We formulate a low-energy theory for the magnetic interactions between electrons in the multi-band Hubbard model under non-equilibrium conditions determined by an external time-dependent electric field which simulates laser-induced spin…

We study the spinful fermionic Haldane-Hubbard model at half filling using a combination of quantum cluster methods: cluster perturbation theory (CPT), the variational cluster approximation (VCA), and cluster dynamical mean-field theory…

Time-reversal symmetric topological insulator is a novel state of matter that a bulk-insulating state carries dissipationless spin transport along the surfaces, embedded by the $Z_2$ topological invariant. In the noninteracting limit, this…

The nature of a metal--insulator transition tuned by external gates in quantum Hall (QH) systems with point constrictions at integer bulk filling, as reported in recent experiments of Roddaro et al. [1], is addressed. We are particularly…

The effect of on-site electron-electron repulsion $U$ in a band insulator is explored for a bilayer Hubbard Hamiltonian with opposite sign hopping in the two sheets. The ground state phase diagram is determined at half-filling in the plane…

We investigate a multi-orbital extension of the periodic Anderson model with particular emphasis on electron correlations including orbital fluctuations. By means of a linearized version of the dynamical mean-field theory, we compute the…

We consider the Kane-Mele model with spin-orbit coupling supplemented by a Hubbard U term. On the basis of projective auxiliary field quantum Monte Carlo simulations on lattice sizes up to 15 x 15, we map out the phase diagram. The quantum…

A detailed study of electronic phase transitions in the ionic Hubbard model at half filling is presented. Within the dynamical mean field approximation a series of transitions from the band insulator via a metallic state to a Mott-Hubbard…