We employ dynamical mean-field theory (DMFT) with a quantum Monte Carlo atomic solver to investigate the finite-temperature Mott transition in the Hubbard model with nearest-neighbor hopping on a triangular lattice at half-filling. We estimate the value of the critical interaction to be ${U}_{c}=12.0\ifmmode\pm\else\textpm\fi{}0.5$ in units of the hopping amplitude $t$ through the evolution of the magnetic moment, spectral function, internal energy, and specific heat as the interaction $U$ and temperature $T$ are varied. This work also presents a comparison between DMFT and finite-size determinant quantum Monte Carlo calculations and a discussion of the advantages and limitations of both methods.We employ dynamical mean-field theory (DMFT) with a quantum Monte Carlo atomic solver to investigate the finite-temperature Mott transition in the Hubbard model with nearest-neighbor hopping on a triangular lattice at half-filling. We estimate the value of the critical interaction to be ${U}_{c}=12.0\ifmmode\pm\else\textpm\fi{}0.5$ in units of the hopping amplitude $t$ through the evolution of the magnetic moment, spectral function, internal energy, and specific heat as the interaction $U$ and temperature $T$ are varied. This work also presents a comparison between DMFT and finite-size determinant quantum Monte Carlo calculations and a discussion of the advantages and limitations of both methods.

arXiv:cond-mat/0604609Physical Review BAug 30, 200654 citations

Vortex crystallisation in classical field theory

Lobo, Carlos, Alice Sinatra, Yvan Castin

We show that the formation of a vortex lattice in a weakly interacting Bose condensed gas can be modeled with the nonlinear Schrodinger equation for both T=0 and finite temperatures without the need for an explicit damping term. Applying a weak rotating anisotropic harmonic potential we find numerically that the turbulent dynamics of the field produces an effective dissipation of the vortex motion and leads to the formation of a lattice. For T=0 this turbulent dynamics is triggered by an already known rotational dynamic instability of the condensate. For finite temperatures, noise is present at the start of the simulation and allows the formation of a vortex lattice at a lower rotation frequency, the Landau frequency. These two regimes have different vortex dynamics. We show that the multimode interpretation of the classical field is essential.We show that the formation of a vortex lattice in a weakly interacting Bose condensed gas can be modeled with the nonlinear Schrodinger equation for both T=0 and finite temperatures without the need for an explicit damping term. Applying a weak rotating anisotropic harmonic potential we find numerically that the turbulent dynamics of the field produces an effective dissipation of the vortex motion and leads to the formation of a lattice. For T=0 this turbulent dynamics is triggered by an already known rotational dynamic instability of the condensate. For finite temperatures, noise is present at the start of the simulation and allows the formation of a vortex lattice at a lower rotation frequency, the Landau frequency. These two regimes have different vortex dynamics. We show that the multimode interpretation of the classical field is essential.

arXiv:cond-mat/0301628Jan 31, 20031 citation

Itinerant ferromagnetism in an SU(3) Fermi-Hubbard model at finite temperatures: A dynamical mean-field theory study

Juntaro Fujii, Kazuki Yamamoto, Akihisa Koga

We investigate an SU(3) Fermi-Hubbard model on a hypercubic lattice at finite temperatures, combining dynamical mean-field theory with continuous-time quantum Monte Carlo simulations. Taking strong correlations into account carefully, we find a ferromagnetically ordered state, in which one of the three components becomes dominant, when holes are doped away from one-third filling. Furthermore, we demonstrate that this ferromagnetically ordered phase undergoes a first-order transition to a paramagnetic state. We clarify the stability of the ferromagnetically ordered state against interaction strength, hole doping, and temperatures. The relevance of generalized Nagaoka ferromagnetism is also addressed, by comparing the results on the Bethe lattice.We investigate an SU(3) Fermi-Hubbard model on a hypercubic lattice at finite temperatures, combining dynamical mean-field theory with continuous-time quantum Monte Carlo simulations. Taking strong correlations into account carefully, we find a ferromagnetically ordered state, in which one of the three components becomes dominant, when holes are doped away from one-third filling. Furthermore, we demonstrate that this ferromagnetically ordered phase undergoes a first-order transition to a paramagnetic state. We clarify the stability of the ferromagnetically ordered state against interaction strength, hole doping, and temperatures. The relevance of generalized Nagaoka ferromagnetism is also addressed, by comparing the results on the Bethe lattice.

arXiv:2505.12704Physical review. B./Physical review. BSep 3, 20252 citations

t

through the evolution of the magnetic moment, spectral function, internal energy, and specific heat as the interaction

U

and temperature

T

are varied. This work also presents a comparison between DMFT and finite-size determinant quantum Monte Carlo calculations and a discussion of the advantages and limitations of both methods.