HYDRODYNAMIC APPROACH TO NOISE SPECTRA IN UNIPOLAR SEMICONDUCTOR STRUCTURES

By using a closed hydrodynamic approach coupled with the field-impedan ce method we evaluate the spectra of the small-signal impedance (admit tance) and of the voltage (current) density of submillimeter n+nn+ dio de generators. The calculations, which are performed for the case of I nP with applied fields near the onset of self-oscillations, indicate t he presence of a sharp peak of the current spectral density at the gen eration frequency.