Finite-temperature properties of amorphous silicon

Ab initio local-orbital quantum molecular dynamics is used to study the finite-temperature properties of amorphous silicon. Using two structural models of a-Si with 63 and 216 atoms, we examine the structure and temperature dependence of conduction and valence band tails. An explanation is suggested for the recent experimental observations of an asymmetry in the temperature dependence of the band-tail widths of the conduction and valence bands in a-Si. Finally, we conect these simulations to other theoretical descriptions of band tailing.