Density of electronic states in density-wave compounds with imperfect nesting

TL;DR

This paper investigates how imperfect nesting affects the electronic density of states and conductivity in density-wave materials, revealing singularities and renormalization effects that align with experimental observations in quasi-1D metals.

Contribution

It introduces a simple 2D tight-binding model to analyze the impact of imperfect nesting on density-wave states, highlighting novel singularities and their influence on superconductivity.

Findings

Imperfect nesting causes unusual singularities in the density of states.

Renormalization of the superconducting critical temperature occurs due to these singularities.

Calculated conductivity matches experimental data on rare-earth tritellurides and similar materials.

Abstract

We study the effects of imperfect nesting in a simple 2D tight-binding model on the electronic properties in the density-wave (DW) state. The discussed model reflects the main features of quasi-1D metals, where the DW emerges. We show that an imperfect nesting leads to unusual singularities in the quasi-particle density of states, leading to a strong renormalization of the superconducting critical temperature. We also compute the conductivity tensor of the normal state and obtain a satisfactory agreement with the experimental data on rare-earth tritellurides and many other DW materials.