Role of bimolecular recombination in picosecond photoinduced absorption of hydrogenated amorphous silicon

Abstract This paper demonstrates that recent measurements of the picosecond decay of photoinduced absorption (PA) in hydrogenated amorphous silicon can be explained by dispersive bimolecular recombination of band-tail electrons with holes trapped in the valence band and/or midgap states. The results explain the dependence of the decay on temperature and intensity and provide a framework for analysing PA decays over a range of intensities and trap densities.