Optical Properties of Graphene in the Terahertz Region

Abstract

This thesis explores the substrate-dependent charge carrier dynamics of large area graphene fi lms. Using terahertz spectroscopy, we measure conductivity spectra of graphene supported by seven distinct substrates, and extract their transport properties (carrier scattering time, doping density, and carrier mobility) within the Drude model. We find that graphene supported by distinct substrates exhibit signi cantly different transport properties. We propose that graphene fi lms supported by substrates with less charged impurities exhibit longer scattering times, and enhanced carrier mobilities, emphasizing the importance of the graphene-substrate interaction for optimization of device performance. These results will be signi cant for the effective integration of graphene into future technologies where an optimal carrier mobility is desired.