Transient photoresponse in Pr0.7Ca0.3MnO3 thin films at room temperature

Abstract

Photoresponse characteristics of Pr0.7Ca0.3MnO3 thin films were investigated under different applied voltages and excitation light energy densities at room temperature.The transient resistance change of 92.3% and response time of～36ns were observed under the excitation with a 532 nm laser pulse of 7ns duration at a light energy density of 275.16mJ/cm2.Both the resistance change and response time showed nonlinear behavior as a function of the light energy density, and the resistance and the response time were reduced when the intensity increased. However, the applied voltage had almost no effect on the photoresponse at room temperature. The phenomena are explained in terms of the photoinduced nonequilibrium insulator-to-metal transition in the film, which may have potential applications in optoelectronic devices.