Electrodynamic Concepts of Wave Interactions in Thin-Film Semiconductor Structures. II

Abstract

This chapter discusses the electrodynamic concepts of wave interactions in thin-film semiconductor structures. The analysis of electrodynamic concepts of wave interactions showed that up to now the basic theoretical problems necessary for the study of wave processes in thin-film semiconductor structures (TFSS) are sufficiently developed: (1) the boundary conditions on charge carrier stream surfaces in nondegenerate semiconductor plasmas for different physical situations distinguishing by a degree of the influence of diffusion, surface states and charged layers, and transverse displacement of stream boundary; (2) the normal mode orthogonality for different subsystems (electromagnetic, ferromagnetic, acoustic ones and carrier streams) included in TFSS; (3) The excitation of normal mode by external sources and the mutual coupling between the subsystems of TFSS; and (4) the power relations and the normalization of normal modes. Dispersion properties of thin semiconductor films without magnetic field are studied and allow one to understand the mechanism of operation of thin-film semiconductor traveling-wave amplifier (TWA). Effects of magnetic field on carrier-wave spectrum for different models of carrier-stream boundary can be investigated on the basis of the obtained theoretical relations. This chapter concludes that the developed theoretical method of normal and coupled modes allows one to analyze wave interactions in different kinds of thin-film semiconductor structures.