Electrons and holes in amorphous silicon

Abstract

We have used the equation-of-motion method to simulate the motion of wave packets representing electrons in the presence of a potential gradient for both crystalline and amorphous silicon. This is used to determine the sign of the electron effective mass for various energies in the valence and conduction band. There is a close correspondence between the crystalline and amorphous results and there is therefore no indication of the double-sign anomaly of the Hall coefficient.