Limitation and suppression of hot-electron fluctuations in submicrometer semiconductor structures

We present the results of theoretical investigations of fluctuations of hot electrons in submicrometer active regions, where the dimension 2d of the region is comparable to the electron-energy relaxation length ${\mathit{L}}_{\mathrm{\varepsilon }}$. In the low-frequency limit, we find an exact solution of the Langevin equation for space-dependent electron fluctuations. The numerical calculations of spectral densities of fluctuations of the electron temperature and current are presented. The fluctuations depend on the sample thickness; with 2d${\mathit{L}}_{\mathrm{\varepsilon }}$ a suppression of fluctuations arises in the range of fluctuation frequencies ω≪${\mathrm{\tau }}_{\mathrm{\varepsilon }}^{\mathrm{-}1}$, where ${\mathrm{\tau }}_{\mathrm{\varepsilon }}$ is the electron-energy relaxation time.