Low-frequency Magneto-optical Spectra of Bilayer Bernal Graphene

TL;DR

This study investigates the low-frequency magneto-optical spectra of bilayer Bernal graphene, revealing complex absorption features influenced by interlayer interactions and providing insights into electronic properties and hopping integrals.

Contribution

It presents a detailed analysis of the magneto-optical spectra of bilayer Bernal graphene, highlighting the effects of interlayer interactions and wave function characteristics on optical absorption.

Findings

Identification of two groups of Landau levels based on wave functions

Four types of optical absorption peaks with complex selection rules

Dependence of spectra on magnetic field strength differs from monolayer graphene

Abstract

The low-frequency magneto-optical absorption spectra of bilayer Bernal graphene are studied within the tight-binding model and gradient approximation. The interlayer interactions strongly affect the electronic properties of the Landau levels (LL's), and thus enrich the optical absorption spectra. According to the characteristics of the wave functions, the low-energy LL's can be divided into two groups. This division results in four kinds of optical absorption peaks with complex optical selection rules. Observing the experimental convergent absorption frequencies close to zero magnetic field might be useful and reliable in determining the values of several hopping integrals. The dependence of the optical absorption spectra on the field strength is investigated in detail, and the results differ considerably from those of monolayer graphene.