Millimeter wave transmission spectroscopy of gated two-dimensional hole systems

We developed a differential transmission to study cyclotron resonance of GaAs/AlxGa1-xAs two-dimensional hole samples. The technique utilizes a modulated AuPd gate isolated by a Si3N4 dielectric from the sample, which is irradiated opposite the gate by millimeter waves ranging from 2 to 40GHz. This technique effectively removes the background signal and yields a hole effective mass of 0: 41m(e) with a cyclotron scattering time of similar to 20 ps, consistent with the previous results using different techniques. (C) 2012 American Institute of Physics. {[}http://dx.doi.org/10.1063/1.4711772]