Parametric interaction of space-charge waves in thin-film semiconductor structures

The general theory of parametric coupling between space-charge waves and dr ifting charge carriers in thin-film semiconductor structures has been worke d out. This theory is applicable, in particular, to n-GaAs and n-InP semico nductors with negative differential conductance due to intervalley electron transitions under high electric fields. We started from the electrodynamic theory of waveguide excitation by extraneous currents, which was extended for arbitrary waveguide structures with composite active media. Our theory makes it possible to study parametric interaction between space-charge wave s in semiconductor films with regard for boundary conditions, diffusion, th e anisotropy and the frequency dispersion of the differential electron mobi lity, as well as the multifrequency and multimode nature of a wave process in thin-film structures. (C) 2000 MAIK "Nauka/Interperiodica".