It is described a kinetic theory providing bases for an analytical treatment of nonlinear quantum transport. It is founded on a nonequilibrium statistical ensemble formalism, which constitutes a soundly approach for the study of dissipative many-body systems driven arbitrarily away from equilibrium. This theory is applied to the study of transport of charge in n- and p- type doped polar semiconductors. Evolution of the carriers’ quasitemperature and mobility as well as of the relaxation times for energy and momentum are derived. Some comparison with experimental data is done.

A theoretical study on the electron drift velocity and some nonequilibrium thermodynamic characteristics of wurtzite GaN, AlN, and InN is presented. It is based on a nonlinear quantum kinetic theory which provides a description of the dissipative phenomena developing in the system. The ultrafast time evolution of the electron drift velocity and quasitemperature is obtained, and overshoot effects are evidenced on both. The overshoot onsets are shown to occur at 20 kV/cm in GaN, 60 kV/cm in AlN, and 10 kV/cm in InN, electric field intensities which are considerably smaller than those that have been recently derived resorting to Monte Carlo simulations.

We describe the formalism of statistical irreversible thermodynamics constructed based on Zubarev’s nonequilibrium statistical operator (NSO) method, which is a powerful and universal tool for...

This communication presents a comparative study on the charge transport (in transient and steady state) in bulk n-type doped SiC-polytypes: 3C-SiC, 4H-SiC and 6H-SiC. The time evolution of the basic macrovariables: the “electron drift velocity” and the “non-equilibrium temperature” are obtained theoretically by using a Non-Equilibrium Quantum Kinetic Theory, derived from the method of Nonequilibrium Statistical Operator (NSO). The dependence on the intensity and orientation of the applied electric field of this macrovariables and mobility are derived and analyzed. From the results obtained in this paper, the most attractive of these semiconductors for applications requiring greater electronic mobility is the polytype 4H-SiC with the electric field applied perpendicular to the c-axis.

We consider the transport properties of polar direct-gap semiconductors in an electric field, specializing the numerical calculation of the general theory to the case of n-doped III-nitrides, in particular, GaN, AlN, and InN. The nonequilibrium thermodynamic state of these materials—characterized by the variables so-called quasitemperature, quasichemical potential, and drift velocity of the carriers, and the quasitemperatures of longitudinal optical and acoustical phonons—is studied. The evolution equations of these variables—which are highly nonlinear—are derived, and the transient regime and the ensuing steady state are analyzed. The nonlinear transport is characterized and its main properties are discussed. In one case comparison with a recent Monte Carlo calculation is made and good agreement is obtained. In this paper we mainly consider the ultrafast transient, and in the following paper the steady state.

The case of n-doped direct gap polar semiconductors in the presence of moderate to high electric fields is considered. The study is centered on the theoretical analysis of the behavior of LO phonons generated by drifting electrons. The emergence of a kind of “resonance” (or “overheating”) in the LO-phonon distribution which is centered on an off-center region of the Brillouin zone is evidenced. It consists in a preferential concentration of nonthermal populations of LO phonons in the form of a lobular distribution with its axis along the direction of the electric field. Numerical calculations performed for the case of strongly polar GaN accompanied with descriptive figures are presented.