Photocurrent Transient Spectroscopy: Measurement of the Density of Localized States in a -As 2 Se 3

TLDR: In this article, the multiple-trapping mechanism was used to explain photo-induced optical absorption transients in a unified way with the multiple trapping mechanism, and transient photoconductivity provided a spectroscopy of the density of localized states.

Abstract: Measurements of transient photoinduced optical absorption in $a$-${\mathrm{As}}_{2}$${\mathrm{Se}}_{3}$ show that carriers thermalize within a distribution of localized states in the band gap. Photocurrent as well as photoinduced optical absorption transients are explained in a unified way with the multiple-trapping mechanism. Under such circumstances, transient photoconductivity provides a spectroscopy of the density of localized states.