Excitation wavelength dependence of photoinduced phase transition in polycrystalline AgI at room temperature

Abstract

Excitation wavelength dependence of the photocurrent and the photoinduced change in bulk resistance has been investigated at room temperature for the polycrystalline AgI using steady state photocurrent measurement method and impedance spectroscopy. A small decrease of the bulk resistance is induced by 308 nm excitation, and the bulk resistance further decreases with 450 nm excitation following the 308 nm excitation. The photoinduced reversible switching in bulk resistance between 308 nm excitation and 450 nm excitation has been interpreted in terms of the photoinduced phase transition in the polycrystalline AgI, and these properties are obtained only in the polycrystalline β-AgI. © 2009 IOP Publishing Ltd.