Fluctuations in anisotropic semiconductors related with carrier drift

In a semiconductor crystal with the Si type band structure electric noise is studied related with the ambipolar drift of carriers in the presence of uniaxial deformation perpendicular to a surface of the sample in the form of a plate. Deformation causes anisotropy of carrier mobility. The spectrum of intrinsic oscillations of an electron-hole plasma is shown to be sensitive to the mobility anisotropy and to deformation, consequently. Spectral density of the noise is investigated against the plate thickness and the location of detecting contacts. It follows from the results obtained that not only the quantity but also the character of the frequency dependence of the spectral noise density vary under the effect of deformation. Investigation of the noise spectral density as a function of pressure and thickness gives the possibility to judge frequency and attenuation of different modes of intrinsic oscillations of an electron-hole plasma