Electronic state of a doped Mott-Hubbard insulator at finite temperatures studied using the dynamical mean-field theory

TL;DR

This study uses dynamical mean-field theory to analyze the electronic states of doped Mott-Hubbard insulators at finite temperatures, revealing spectral weight redistributions, coexistence of quasiparticle peaks with Hubbard bands, and a crossover to a bad metal state.

Contribution

It provides new insights into the finite temperature electronic structure and phase behavior of doped Mott insulators using advanced theoretical modeling.

Findings

Spectral weight redistributions with doping in antiferromagnetic and paramagnetic phases

Existence of a metallic antiferromagnetic state with quasiparticle peaks and Hubbard bands

Identification of a crossover to a bad metal state at high temperatures and low doping

Abstract

We study the electronic state of the doped Mott-Hubbard insulator within Dynamical Mean Field Theory. The evolution of the finite temperature spectral functions as a function of doping show large redistributions of spectral weight in both antiferromagnetic and paramagnetic phases. In particular, a metallic antiferromagnetic state is obtained with a low frequency Slater-splitted quasiparticle peak coexisting with Hubbard bands. In the high temperature paramagnetic metallic phase, upon reducing doping, the system has a crossover through a ``bad metal'' state characterized by an anomalous shift of the quasiparticle peak away from the Fermi energy. We find that the {\it charge} compressibility of the antiferromagnetic metal is dramatically enhanced upon approaching the second order N\'eel line.