Fast excited state diffusion in a-As_2Se_3 chalcogenide films

摘要

Transient grating experiments after optical band-gap pulsed illumination of amorphous a-As_2Se_3 thin films reveal the existence of a well defined transport process occurring on length- and time-scales of the order of micrometers and microseconds, respectively. We tentatively assign this fast process, corresponding to a mobility of 0.04 ± 0.005 cm~2 V~(-1) s~(-1) to the diffusion of photoexcited charge carriers with microsecond lifetime.