Carrier Nonradiative Recombination in Sb2Se3

Antimony selenide (Sb2Se3) is emerging as an optically active material for optoelectronic devices. Understanding the carrier nonradiative recombination processes in Sb2Se3 is crucial for the improvement of devices' performance. In this work, the carrier nonradiative recombination was investigated by transient absorption spectrum on the broad time scale from hundred femtoseconds to several microseconds. The evolution of the transient absorption spectrum has been associated with the free carrier and trapped carrier recombination process. Our temperature varying transient absorption spectrum measurement also confirmed that the free carrier recombination in Sb2Se3 is insensitive to temperature. Finally, the rate equation for free carrier recombination in Sb2Se3 was discussed. To simulate the free carrier decay well and interpret its temperature-insensitive character, trap-assisted Auger recombination was introduced into the rate equation.