Dynamic conductivity of an InAs two-dimensional electron gas measured using terahertz time-domain spectroscopy

Abstract We utilized a coherent terahertz time-domain spectroscopy system to measure the dynamic conductivity of an InAs two-dimensional electron gas. Based on the theoretical transmission analysis, the real and imaginary parts of the complex conductivity of the sample were extracted from the transmitted terahertz time-domain waveforms. We also measured the sample at low temperatures and fitted the real and imaginary parts of the conductivity with the Drude model to extract its densities and mobilities. The dominant scattering mechanisms are discussed according to the temperature dependence of the extracted densities and mobilities.