Temperature-dependent Drude transport in a two-dimensional electron gas

Abstract

We consider transport of dilute two-dimensional electrons, with temperature between Fermi and Debye temperatures. In this regime, electrons form a nondegenerate plasma with mobility limited by potential disorder. Different kinds of impurities contribute unique signatures to the resulting temperature-dependent Drude conductivity, via energy-dependent scattering. This opens up a way to characterize sample disorder composition. In particular, neutral impurities cause a slow decrease in conductivity with temperature, whereas charged impurities result in conductivity growing as a square root of temperature. This observation serves as a precaution for literally interpreting metallic or insulating conductivity dependence, as both can be found in a classical metallic system.

5 pages, 2 figures, published version

References in corpus (4)

• Substrate-induced band gap opening in epitaxial graphene
• Numbers of donors and acceptors from transport measurements in graphene
• Strongly Enhanced Hole-Phonon Coupling in the Metallic State of the Dilute Two-Dimensional Hole Gas
• Disappearance of the metal-like behavior in GaAs two-dimensional holes below 30 mK