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

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 1 THz, 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 similar to 5x10(-8) W/Hz(1/2); the electronics-limited response time is 10 ns. (c) 2008 American Institute of Physics.