Radiation-induced magnetoresistance oscillations with massive Dirac fermions

Abstract

We report on a theoretical study on the rise of radiation-induced magnetoresistance oscillations in two-dimensional systems of massive Dirac fermions. We study the bilayer system of monolayer graphene and hexagonal boron nitride (h-BN/graphene) and the trilayer system of hexagonal boron nitride encapsulated graphene (h-BN/graphene/h-BN). We extend the radiation-driven electron orbit model that was previously devised to study the same oscillations in two-dimensional systems of Schr\"odinger electrons (GaAs/AlGaAS heterostructure) to the case of massive Dirac fermions. In the simulations we obtain clear oscillations for radiation frequencies in the terahertz and far-infrared bands. %which contrasts with the two-dimensional Schrodinger electrons case, %that are mainly sensitive to microwave frequencies. We investigate also the power and temperatures dependence. For the former we obtain similar results as for Schr\"odinger electrons and predict the rise of zero resistance states. For the latter we obtain a similar qualitatively dependence but quantitatively different when increasing temperature. While in GaAs the oscillations are wiped out in a few degrees, interestingly enough, for massive Dirac fermions, we obtain observable oscillations for temperatures above $100$ K and even at room temperature for the higher frequencies used in the simulations.