Room temperature terahertz detection based on bulk plasmons in antenna-coupled GaAs field effect transistors

Abstract

A first generation of antenna-coupled GaAs metal-semiconductor-field-effect-transistors (MESFETs) is fabricated, modeled, and tested for room-temperature terahertz detection. For fixed excitation frequencies between 0.14 and 1THz, the source-drain current (signal) is monitored as the gate and drain voltages are varied. The signal shows resonances when applied voltages sweep the charge density in the MESFET through values at which the bulk plasmon is resonant with the excitation frequency. For these unoptimized devices, the measured system noise-equivalent power is ∼5×10−8W∕Hz1∕2; the electronics-limited response time is 10ns.