Electronic consequences of the mutual presence of thermal and structural disorder

We investigate the simultaneous presence of topological and thermal disorde r in amorphous silicon. We find that localized electronic states are very s ensitive to moderate amounts of thermal disorder: for a given gap or band t ail electronic eigenstate, both the fraction of the total charge on a given site as well as the energy eigenvalue can vary greatly with small (thermal ly accessible) changes to the positions of the atoms. This observation, whi ch is almost certainly relevant to any disordered insulator including glass es, has important implications to the microscopic theory of transport, opti cal properties, and doping, as well as existing models of defect kinetics.