Study of the Hubbard model on the triangular lattice using dynamical cluster approximation and dual fermion methods
arXiv:0807.1683 · doi:10.1103/PhysRevB.78.205117
Abstract
We investigate the Hubbard model on the triangular lattice at half-filling using the dynamical cluster approximation (DCA) and dual fermion (DF) methods in combination with continuous-time quantum Monte carlo (CT QMC) and semiclassical approximation (SCA) methods. We study the one-particle properties and nearest-neighbor spin correlations using the DCA method. We calculate the spectral functions using the CT QMC and SCA methods. The spectral function in the SCA and obtained by analytic continuation of the Pade approximation in CT QMC are in good agreement. We determine the metal-insulator transition (MIT) and the hysteresis associated with a first-order transition in the double occupancy and nearest-neighbor spin correlation functions as a function of temperature. As a further check, we employ the DF method and discuss the advantages and limitation of the dynamical mean field theory (DMFT), DCA and recently developed DF methods by comparing Green's functions. We find an enhancement of antiferromagnetic (AF) correlations and provide evidence for magnetically ordered phases by calculating the spin susceptibility.
6 pages, 7 figures
References in corpus (12)
- Quantum Monte Carlo Impurity Solver for Cluster DMFT and Electronic Structure Calculations in Adjustable Base
- Cluster Dynamical Mean Field Theory of the Mott Transition
- Mott Transition, Antiferromagnetism, and d-wave Superconductivity in Two-Dimensional Organic Conductors
- Gapless quantum spin liquid, stripe and antiferromagnetic phases in frustrated Hubbard models in two dimensions
- Local Order and the gapped phase of the Hubbard model: a plaquette dynamical mean field investigation
- Mott transition in Kagomé lattice Hubbard model
- Finite temperature Mott transition in Hubbard model on anisotropic triangular lattice
- Quasiparticles at the verge of localization near the Mott metal-insulator transition in a two-dimensional material
- Dual Fermion Approach to Susceptibility of Correlated Lattice Fermions
- Dynamical mean field study of the Mott transition in the half-filled Hubbard model on a triangular lattice
- Electronic Properties of the Hubbard Model on a Frustrated Triangular Lattice
- Fictive Impurity Approach to Dynamical Mean Field Theory: a Strong-Coupling Investigation