Exact solution of the spectrum and magneto-optics of multilayer hexagonal graphene

Abstract

We demonstrate that by decoupling the interlayer interactions, N-layer hexagonal graphene is decomposed into the N independent subsystems. Each subsystem, exactly described by a 2 × 2 matrix, is treated as a renormalized graphene with the renormalized site energy and intralayer interaction. The analytical form of the energy dispersions and wave functions of each renormalized graphene is easily obtained. The study reveals the origin of electron-hole asymmetry, and how it is caused by the interlayer interaction between different sublattices at adjacent layers. The monolayer-graphene-like characteristics allow us to describe Landau-level energies and magneto-optical absorption spectra of each renormalized graphene based on the effective mass model. There are N sets of Landau levels in the energy spectra of the N-layer hexagonal graphene. The magneto-optical spectra exhibit N groups of Landau-peaks. Each group of Landau-peaks follows the same optical selection as that of a monolayer graphene.