Quantum magneto-optics of graphite family

TL;DR

This paper investigates the optical conductivity of graphene, bilayer graphene, and graphite under strong magnetic fields, analyzing electron transitions, effects of trigonal warping, and magneto-optical phenomena like Faraday rotation.

Contribution

It provides an analytical evaluation of dynamical conductivities, incorporates trigonal warping effects within perturbation and semiclassical approaches, and fits parameters using experimental data.

Findings

Optical conductivity peaks explained by electron transitions.

Trigonal warping effects are significant for certain magnetic field regimes.

Magneto-optical effects like Faraday rotation are quantitatively analyzed.

Abstract

The optical conductivity of graphene, bilayer graphene, and graphite in quantizing magnetic fields is studied. Both dynamical conductivities, longitudinal and Hall's, are analytically evaluated. The conductivity peaks are explained in terms of electron transitions. We have shown that trigonal warping can be considered within the perturbation theory for strong magnetic fields larger than 1 T and in the semiclassical approach for weak fields when the Fermi energy is much larger than the cyclotron frequency. The main optical transitions obey the selection rule with \Deltan = 1 for the Landau number n, however the \Deltan = 2 transitions due to the trigonal warping are also possible. The Faraday/Kerr rotation and light transmission/reflection 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 strong magnetic fields.