Quantum magneto-optics of graphite with trigonal warping

TL;DR

This paper analytically studies the optical conductivity of graphite under strong magnetic fields, highlighting the effects of trigonal warping on electron transitions and optical properties like Kerr rotation.

Contribution

It introduces a perturbation theory approach to account for trigonal warping in graphite's magneto-optical response at high magnetic fields.

Findings

Trigonal warping affects optical transitions with small probability for Δn=2.

Optical conductivity peaks are explained by electron transitions.

Kerr rotation and reflectivity are calculated for graphite in quantizing magnetic fields.

Abstract

The optical conductivity of graphite in quantizing magnetic fields is studied. Both the dynamical conductivities, longitudinal as well as Hall's, are analytically evaluated. The conductivity peaks are explained in terms of electron transitions. We have shown that the trigonal warping in graphite can be considered within the perturbation theory at the strong magnetic field larger than 1 T approximately. The main optical transitions obey the selection rule with $\Delta n=1$ for the Landau number $n$, however the $\Delta n=2$ transitions due to the trigonal warping with the small probability are also essential. The Kerr rotation and reflectivity in graphite in the quantizing magnetic fields are calculated. Parameters of the Slonczewski--Weiss--McClure model are used in the fit taking into account the previous dHvA measurements and correcting some of them for the case of the strong magnetic fields.