Non-Equilibrium Electrons

Abstract

The structure of the kinetic equation for the electrons interacting with bosons (phonons or photons) is similar to the one for the case of electron-impurity system considered in Chapter 2. However, a consideration of electron scattering with emission or absorption of bosons leads to a more sophisticated collision integral, because the Pauli principle is essential for inelastic scattering. This kinetic equation is derived by analogy to the case of non-equilibrium bosons considered in Chapter 4. The collision integral for inelastic scattering derived below describes the energy relaxation of electron system, the evolution of the occupation numbers of different electron states, etc. For this reason, it has numerous applications for strongly non-equilibrium electron systems. In this chapter we discuss the distribution of the electrons heated by a static electric field or high-frequency field of laser radiation in the cases when either electron-phonon or electron-electron collisions dominate. In the latter case, it is convenient to introduce the energy balance equations. Besides, we consider the interaction of non-equilibrium electrons with photons, in particular, in the process of radiative interband recombination. This process is described by the density balance equations. In this connection, we also study the phonon-assisted redistribution of electron population between the subbands in nanostructures of different dimensionalities.