Optical Conductivity of the t-J model within Cluster Dynamical Mean Field Theory

TL;DR

This paper investigates the optical conductivity of the t-J model across different doping levels and temperatures using Cluster Dynamical Mean Field Theory, revealing doping-independent optical mass near half filling and contrasting kinetic energy behaviors in different regimes.

Contribution

It applies the Extended Dynamical Cluster Approximation to analyze optical properties of the t-J model, highlighting doping-dependent kinetic energy changes and spectral weight transfers.

Findings

Optical mass is doping independent near half filling.

Kinetic energy decreases in the overdoped superconducting transition.

Spectral weight transfers occur over a broad frequency range.

Abstract

We study the evolution of the optical conductivity in the t-J model with temperature and doping using the Extended Dynamical Cluster Approximation. The cluster approach results in an optical mass which is doping independent near half filling. The transition to the superconducting state in the overdoped regime is characterized by a decrease in the hole kinetic energy, in contrast to the underdoped side where kinetic energy of holes increases upon superfluid condensation. In both regimes, the optical conductivity displays anomalous transfers of spectral weight over a broad frequency region.