Search

The purpose of this study is to apply the distribution function formalism to the problem of electronic transport in open systems, and numerically solve the kinetic equation with a dissipation term. This term is modeled within the relaxation time approximation, and contains two parts, corresponding to elastic or inelastic processes. The collision operator is approximated as a sum of the semiclassical energy dissipation term, and the momentum relaxation term which randomizes momentum but does not change energy. As a result, the distribution of charge carriers changes due to the dissipation processes, which has a profound impact on the electronic transport through the simulated region discussed in terms of the current–voltage characteristics and their modification caused by the scattering.

Using the phase space approach, we consider the dynamics of a quantum particle in an isolated confined quantum system with three different potential energy profiles. We solve the Moyal equation of motion for the Wigner function with the highly efficient spectral split-operator method. The main aim of this study is to compare the accuracy of the used algorithm by analysis of the total energy expectation value, in terms of the deviation from its exact value. This comparison is performed for the second and fourth order factorizations of the time evolution operator.

A mathematical model of the investigated semiconductor core-shell nanowire transistor with all-around gate, computation methods and calculated transport characteristics of the device are presented. The influence of applied gate voltage and drain-source voltage on the potential energy profile of the system is determined, electric current flowing through it is calculated and dependence of operation regime of the device on these voltages is discussed.