Photoelectric Characteristic of La_0.9Sr_0.1MnO₃/SrNb_0.01Ti_0.99O₃ p--n eterojunctions

Good rectifying current--voltage characteristics and nanosecond photoelectric effects are observed in the p--n heterojunctions of La_0.9Sr_0.1MnO₃/SrNb_0.01Ti_0.99O₃ fabricated by laser molecular beam epitaxy. The rise time is about 26ns and the full width at half maximum is about 125ns for the open-circuit photovoltaic pulses when the La_0.9Sr_0.1MnO₃/ film in the heterojunction is irradiated by a laser operated at wavelength 308nm with pulse duration of about 25ns. A qualitative explanation is presented, based on an analysis of the photoelectric effect of p--n heterojunction.