Optical conductivity of the infinite-dimensional Hubbard model

TL;DR

This paper uses Monte Carlo and maximum entropy methods to calculate the optical conductivity of the infinite-dimensional Hubbard model, revealing anomalies similar to those in cuprate superconductors, linked to quasiparticle band formation.

Contribution

It demonstrates that key optical anomalies observed in high-temperature superconductors are inherent to the strongly correlated Hubbard model in high dimensions.

Findings

Optical conductivity shows a linear-in-temperature Drude width.

Drude weight increases linearly with doping.

Presence of a temperature and doping-dependent mid-IR peak.

Abstract

A Monte Carlo-maximum entropy calculation of the optical conductivity of the infinite-dimensional Hubbard model is presented. We show that the optical conductivity displays the anomalies found in the cuprate superconductors, including a Drude width which grows linearly with temperature, a Drude weight which grows linearly with doping, and a temperature and doping-dependent mid-IR peak. These anomalies arise as a consequence of the dynamical generation of a quasiparticle band at the Fermi energy as T -> 0, and are a generic property of the strongly correlated Hubbard model in all dimensions greater than one.