Fast multi-orbital equation of motion impurity solver for dynamical mean field theory

Abstract

We propose a fast multi-orbital impurity solver for the dynamical mean field theory (DMFT). Our DMFT solver is based on the equations of motion (EOM) for local Green's functions and constructed by generalizing from the single-orbital case to the multi-orbital case with inclusion of the inter-orbital hybridizations and applying a mean field approximation to the inter-orbital Coulomb interactions. The two-orbital Hubbard model is studied using this impurity solver within a large range of parameters. The Mott metal-insulator transition and the quasiparticle peak are well described. A comparison of the EOM method with the QMC method is made for the two-orbital Hubbard model and a good agreement is obtained. The developed method hence holds promise as a fast DMFT impurity solver in studies of strongly correlated systems.

25 pages, 12 figures

References in corpus (8)

• A continuous-time solver for quantum impurity models
• Magnetism and Charge Dynamics in Iron Pnictides
• Modeling the Unconventional Superconducting Properties of Expanded A${}_3$C${}_{60}$ Fullerides
• Orbital-selective Mott transitions in the anisotropic two-band Hubbard model at finite temperatures
• Decoupling method for dynamical mean field theory calculations
• A fast impurity solver based on equations of motion and decoupling
• Validity of Equation-of-Motion Approach to Kondo Problem in the Large-$N$ limit
• A Fast Impurity Solver Based on Gutzwiller variational approach

Cited by in corpus (3)

• Projective Truncation Approximation for Equations of Motion of Two-Time Green's Functions
• Kondo physics of the Anderson impurity model by Distributional Exact Diagonalization
• Investigation of on-site inter-orbital single electron hoppings in general multi-orbital systems