Plasmon Enhanced Electron Drag and Terahertz Photoconductance in a Grating-Gated Field-Effect Transistor with Two-Dimensional Electron Channel

摘要

The specific goal for the 1st year was to develop a physical model of the interaction between THz EM radiation and 2D electron channel of the grating-gated field-effect transistor. This physical model has been developed. The model predicts and allows to calculate photo induced dc correction to the source-drain voltage measured in experiment. Calculations demonstrate that dc photovoltage has resonant peaks at plasmon frequencies. Dependence of the peak positions, shape, and amplitude on the frequency, gate voltage, temperature, and FET geometry has been found. Distributions of the non-equilibrium electron density, electric fields, and currents in the 2D channel at resonance have been calculated. The results are in very good qualitative agreement with experiment. Plans for the coming year include numerical simulation of the dc photoresponse for various system designs in order to optimize device parameters and assess its potential as a THz detector.