Calculation of Optical Conductivity of YbB$_{12}$ using Realistic Tight-Binding Model

TL;DR

This paper presents a theoretical calculation of the optical conductivity of YbB$_{12}$, a Kondo insulator, using a realistic tight-binding model and many-body effects, successfully reproducing experimental temperature-dependent spectra.

Contribution

It introduces a calculation method combining a tight-binding model with self-consistent second order perturbation theory for YbB$_{12}$.

Findings

Optical conductivity shape matches experimental data.

Temperature dependence of conductivity is accurately reproduced.

Many-body effects are effectively incorporated.

Abstract

Based on the previously reported tight-binding model fitted to the LDA+U band calculation, optical conductivity of the prototypical Kondo insulator YbB$_{12}$ is calculated theoretically. Many-body effects are taken into account by the self-consistent second order perturbation theory. The gross shape of the optical conductivity observed in experiments are well described by the present calculation, including their temperature-dependences.