Experimental measurements of effective mass in near-surface InAs quantum wells

Near-surface indium arsenide quantum wells have recently attracted a great deal of interest since they can be interfaced epitaxially with superconducting films and have proven to be a robust platform for exploring mesoscopic and topological superconductivity. In this paper, we present magnetotransport properties of two-dimensional electron gases confined to an indium arsenide quantum well near the surface. The electron mass extracted from the envelope of the Shubnikov-de Haas oscillations shows an average effective mass m* = 0.04 at a low magnetic field. Complementary to our magnetotransport study, we employed cyclotron resonance measurements and extracted the electron effective mass in the ultrahigh magnetic-field regime. Both regimes can be understood by considering a model that includes nonparabolicity of the indium arsenide conduction bands.