Fast excited state diffusion in a-As2Se3 chalcogenide films

Transient grating experiments after optical band-gap pulsed illumination of amorphous a-As2Se3 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. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4745612]