相关论文: Field theory for generalized Shastry-Sutherland mo…
We investigate the insulating phases of a frustrated Hubbard model in its strong coupling regime at half-filling. We pay special attention to all the symmetry breaking instabilities that can be described by Dynamical Mean Field Theory…
We study the effect of introducing separable quenched disorder on a non-equilibrium mean-field spin model exhibiting a phase transition to an oscillating state in the absence of disorder, due to non-reciprocal interactions. In the…
Symmetries are important guiding principle for phase transitions. We systematically construct field theory models with local quantum fields that exhibit the following phase transitions: (1) different symmetry protected topological (SPT)…
We study the ground state of the disordered Bose-Hubbard model for spin-1 particles by means of the stochastic mean-field theory. This approach enables the determination of the probability distributions of various physical quantities, such…
Using the approach of low-energy effective field theory, the phase diagram is studied for a mixture of two species of pseudospin-$\1/2$ Bose atoms with interspecies spin-exchange. There are four mean-field regimes on the parameter plane of…
We study magnetically stabilized nematic order for spin-one bosons in optical lattices. We show that the Zeeman field-driven quantum transitions between non-nematic Mott states and quantum spin nematic states in the weak hopping limit are…
A spin version of dynamical mean-field theory is extended for magnetically ordered states in the Heisenberg model. The self-consistency equations are solved with high numerical accuracy by means of the continuous-time quantum Monte Carlo…
We employ a field-theoretical approach to analyze the Bose-Hubbard model on a lattice, with a focus on the low-energy properties across the Mott insulator (MI) to superfluid (SF) transition. Prior approaches approximated the partition…
We study both mean-field and full quantum dynamics of symmetry-breaking transitions (SBTs) in a coupled two-component Bose-Einstein condensate. By controlling s-wave scattering lengths and coupling strength, it is possible to stimulate SBTs…
Exact results in frustrated quantum many-body systems are rare, especially in dimensions higher than one. The Shastry-Sutherland (SS) model stands out as a rare example of a two-dimensional spin system with an exactly solvable dimer singlet…
The spin-Peierls transition in the ground state of a quasi-one-dimensional spin-1/2 Heisenberg model coupled to adiabatic bond phonons is studied using a quantum Monte Carlo (QMC) method. The transition from a gapless Neel state to a…
For lattice models with compact field integration (nonlinear sigma models over compact manifolds and gauge theories with compact groups) and satisfying some discrete symmetry, the change of sign of the bare coupling g_0^2 at zero results in…
We use a recently developed bosonic mean-field theory (MFT) to study the ordered ground states of frustrated Heisenberg antiferromagnets (FHAFM) in two dimensions. We emphasize the role of condensates in satisfying the MF variational…
Photodoped states are widely observed in laser-excited Mott insulators, in which charge excitations are quickly created and can exist beyond the duration of the external driving. Despite the fruitful experimental explorations, theoretical…
Using nonequilibrium dynamical mean-field theory, we compute the time evolution of the current in a Mott insulator after a strong electric field is turned on. We observe the formation of a quasistationary state in which the current is…
We consider the mean-field noisy Kuramoto-Daido model, which is a McKean-Vlasov equation on the circle with bimodal interaction $W(\theta)=\cos\theta+m\cos2\theta$ for $m\ge 0$ and interaction strength $K$, generalizing the celebrated noisy…
We analyze a kinetic Ising model with suppressed bulk noise which is a prominent representative of the generalized voter model phase transition. On the one hand we discuss the model in the context of social systems, and opinion formation in…
We consider quasi-two-dimensional gas of electrons in a typical Si-MOSFET, assuming repulsive contact interaction between electrons. Magnetisation and susceptibility are evaluated within the mean-field approach. Finite thickness of the…
Understanding strongly correlated systems driven out of equilibrium is a challenging task necessitating the simultaneous treatment of quantum mechanics,dynamical constraints and strong interactions. A Mott insulator subjected to a uniform…
We investigate the effect of diagonal disorder on bosons in an optical lattice described by an Anderson-Hubbard model at zero temperature. It is known that within Gutzwiller mean-field theory spatially resolved calculations suffer…