Plasma wave electronics devices for THz detection.

摘要

We report on experimental and theoretical studies of novel semiconductor THz detectors, based on non-linear excitations of plasma waves in a 2D electron gas. A 2D gas channel acts as a resonant "cavity" for the plasma waves, excited by the incident THz radiation, and non-linearity of these waves causes rectification of radiation induced currents.;We study responsivity, sensitivity and response time of plasma wave devices based on Si, GaAs and GaN material systems, and investigate load and bias dependences of the device performance in resonant and non-resonant detection regimes.;We demonstrate that gated and ungated plasma wave field effect transistors can effectively detect THz radiation with reasonable sensitivity comparable with sensitivity of commercially available THz detectors and fast temporal response. The DC electric current in the channel sharply increases the device responsivity and narrows the resonant detection peak. Plasma wave gated and ungated transistors operate as selective and tunable detectors up to room temperature or higher.;These novel THz detectors might find applications in fast, multicolor THz cameras for spectrum analysis, detection, and imaging and will enable numerous applications in radio astronomy, biomedical imaging, homeland security, and explosive detection.