Theory of THz Conductivity in the Pseudogap Phase of the Cuprates: A Pre-Formed Pair Perspective

TL;DR

This paper develops a theoretical model for the THz conductivity in underdoped cuprates considering a pseudogap due to pre-formed pairs, successfully matching experimental data above and below the superconducting transition.

Contribution

It introduces a self-energy based theoretical framework for pseudogap effects on THz conductivity, applicable to various experimental observations in cuprates.

Findings

The model reproduces experimental THz conductivity data.

It explains the pseudogap's impact on conductivity above and below T_c.

The approach unifies interpretation of photoemission and transport measurements.

Abstract

In this paper we deduce transport properties in the presence of a pseudogap associated with precursor superconductivity. Our theoretical analysis is based on the widely adopted self energy expression reflecting this normal state gap, which has appeared in interpretations of photoemission and in other experiments. Thus, it should be generally applicable. Here we address THz conductivity $\sigma (\omega) = \sigma_1(\omega) + i \sigma_2(\omega)$ measurements in the underdoped high temperature superconductors and arrive at reasonable agreement between theory and recent experiment for both $\sigma_1$ and $\sigma_2$ above and below $T_c$.