Infrared magneto-spectroscopy of two-dimensional and three-dimensional massless fermions: A comparison

Abstract

Here, we report on a magneto-optical study of two distinct systems hosting massless fermions - two-dimensional graphene and three-dimensional HgCdTe tuned to the zero band gap condition at the point of the semiconductor-to-semimetal topological transition. Both materials exhibit, in the quantum regime, a fairly rich magneto-optical response, which is composed from a series of intra- and interband inter-Landau level resonances with for massless fermions typical B dependence. The impact of the system's dimensionality and of the strength of the spin-orbit interaction on the optical response is also discussed.