Nanometer size field effect transistors for terahertz detectors.

Nanometer size field effect transistors can operate as efficient resonant or broadband terahertz detectors, mixers, phase shifters and frequency multipliers at frequencies far beyond their fundamental cut-off frequency. This work is an overview of some recent results concerning the application of nanometer scale field effect transistors for the detection of terahertz radiation.

Room temperature detection of sub-terahertz radiation in double-grating-gate transistors.

Room temperature photovoltaic non-resonant detection by large area double-grating-gate InGaP/InGaAs/GaAs heterostructures was investigated in sub-THz range (0.24 THz). Semi-quantitative estimation of the characteristic detection length combined with self-consistent calculations of the electric fields excited in the structure by incoming terahertz radiation allowed us to interpret quantitatively the results and conclude that this detection takes place mainly in the regions of strong oscillating electric field excited in depleted portions of the channel.

Plasma wave oscillations in nanometer field effect transistors for terahertz detection and emission.

The channel of a field effect transistor can act as a resonator for plasma waves propagating in a two-dimensional electron gas. The plasma frequency increases with reduction of the channel length and can reach the terahertz (THz) range for nanometer size transistors. Recent experimental results show these transistors can be potential candidates for a new class of THz detectors and emitters. This work gives an overview of our recent relevant experimental results. We also outline unresolved problems and questions concerning THz detection and emission by nanometer transistors.