Zero temperature metal-insulator transition in the infinite-dimensional Hubbard model

TL;DR

This paper investigates the zero-temperature metal-insulator transition in the infinite-dimensional Hubbard model using Dynamical Mean Field Theory and Numerical Renormalization Group, revealing the transition occurs via the vanishing of a quasiparticle resonance.

Contribution

It provides a detailed analysis of the zero-temperature transition in the Hubbard model using DMFT and NRG, highlighting the role of quasiparticle resonance disappearance.

Findings

Transition occurs via quasiparticle resonance vanishing

Results consistent for Bethe and hypercubic lattices

Spectral functions and self-energy analyzed at zero temperature

Abstract

The zero temperature transition from a paramagnetic metal to a paramagnetic insulator is investigated in the Dynamical Mean Field Theory for the Hubbard model. The self-energy of the effective impurity Anderson model (on which the Hubbard model is mapped) is calculated using Wilson's Numerical Renormalization Group method. Results for quasiparticle weight, spectral function and self-energy are discussed for Bethe and hypercubic lattice. In both cases, the metal-insulator transition is found to occur via the vanishing of a quasiparticle resonance which appears to be isolated from the Hubbard bands.