Phase diagram and dynamic response functions of the Holstein-Hubbard model

Abstract

We present the phase diagram and dynamical correlation functions for the Holstein-Hubbard model at half filling and at zero temperature. The calculations are based on the Dynamical Mean Field Theory. The effective impurity model is solved using Exact Diagonalization and the Numerical Renormalization Group. Excluding long-range order, we find three different paramagnetic phases, metallic, bipolaronic and Mott insulating, depending on the Hubbard interaction U and the electron-phonon coupling g. We present the behaviour of the one-electron spectral functions and phonon spectra close to the metal insulator transitions.

arXiv commentcontribution to the SCES04 conference

References in corpus (4)

• Self-energy-functional approach to systems of correlated electrons
• Gap formation and soft phonon mode in the Holstein model
• First- and Second Order Phase Transitions in the Holstein-Hubbard Model
• Dynamic response functions for the Holstein-Hubbard model

Cited by in corpus (7)

• Phase diagram for the one-dimensional Hubbard-Holstein model: A density-matrix renormalization group study
• Dynamical screening in correlated electron systems - from lattice models to realistic materials
• Metal-insulator transition in the two-orbital Hubbard model at fractional band fillings: Self-energy functional approach
• A coupled cluster framework for electrons and phonons
• Stable bipolarons in open quantum systems
• Heavy-Electron Formation and Bipolaronic Transition in the Anharmonic Holstein Model
• Full configuration interaction quantum Monte Carlo for coupled electron--boson systems and infinite spaces