Pseudogap and charge dynamics in doped cuprates

TL;DR

This paper investigates how charge dynamics and conductivity spectra evolve with doping and temperature in cuprates, revealing the relationship between pseudogap phenomena and unusual spectral features across different doping levels.

Contribution

It provides a microscopic theory explaining the doping and temperature dependence of charge dynamics and spectral features in doped cuprates, especially the pseudogap effects.

Findings

Low-energy non-Drude peak and midinfrared band in underdoped cuprates.

Shift of midinfrared band towards low-energy peak with increased doping.

Recovery of Drude behavior in heavily overdoped regime.

Abstract

Within the microscopic theory of the normal-state pseudogap state, the doping and temperature dependence of the charge dynamics in doped cuprates is studied in the whole doping range from the underdoped to heavily overdoped. The conductivity spectrum in the underdoped and optimally doped regimes contains the low-energy non-Drude peak and unusual midinfrared band. However, the position of the midinfrared band shifts towards to the low-energy non-Drude peak with increasing doping. In particular, the low-energy non-Drude peak incorporates with the midinfrared band in the heavily overdoped regime, and then the low-energy Drude behavior recovers. It is shown that the striking behavior of the low-energy non-Drude peak and unusual midinfrared band in the underdoped and optimally doped regimes is closely related to the emergence of the doping and temperature dependence of the normal-state pseudogap.