Phonon-induced spin depolarization of conduction electrons in silicon crystals

Abstract

In last decade the process of spin relaxation of conduction electrons in semiconductor structures has been widely investigated, in order to use spin polarization as information carrier [1]. However, each initial non-equilibrium orientation decays over time during the transport. Thus, to make feasible the implementation of spin-based electronic devices, the features of spin relaxation at relatively high temperatures, jointly with the influence of transport conditions, should be fully understood [1]. Electrical injection of spin polarization in silicon structures up to room temperature has been experimentally carried out [2]. Despite these promising experimental results, a comprehensive theoretical framework accounting for the spin depolarization process in silicon crystals, in a wide range of temperature values, doping concentration, and amplitude of external fields, is still in a developing stage [3-4]. Here, by using a semiclassical multiparticle Monte Carlo (MC) approach, we simulate spin transport in lightly doped n-type Si samples and calculate the spin lifetimes of conduction electrons. Spin flipping is taken into account through the Elliot-Yafet mechanism, which is dominant in group IV materials.