Subterahertz Emission from a Grid-Gated GaAs/AlGaAs Heterostructure

A subterahertz emission from a grid-gated structure lithographically fabricated on a GaAs/AlGaAs heterostructure was observed at liquid helium temperatures. The frequency of observed emission was equal to about 75 GHz and was almost independent of the voltage biasing the emitter. The Gunn effect is proposed as a possible explanation of the emission. This hypothesis, however, is critically discussed and further experiments are indicated which could lead to a definite identification of the physical mechanism of emission.