Manifestation of pseudogap in ab-plane optical characteristics

TL;DR

This paper presents a model explaining the pseudogap phenomenon in underdoped cuprates, showing how it affects optical properties and spectral weight redistribution over a broad frequency range.

Contribution

It introduces a model linking the pseudogap in the electronic density of states to optical characteristics, providing a robust explanation for observed spectral features.

Findings

The pseudogap causes a triangular peak in the optical self-energy.

Optical spectral weight redistributes over a larger frequency window than in the DOS.

The model successfully describes the impact of the pseudogap on optical conductivity.

Abstract

A model in which a gap forms in the renormalized electronic density of state (DOS) with missing states recovered just above the pseudogap $\Delta_{pg}$, is able to give a robust description of the striking, triangular like, peak seen in the real part of the optical self-energy of underdoped cuprates. We use this model to explore the effect of the pseudogap on the real part of the optical conductivity and on the partial sum rule associated with it. An important result is that the optical spectral weight redistributes over a much larger frequency window than it does in the DOS.