Enhanced photovoltaic effect of La0.8Sr0.2MnO3−δ thin films based on electric field training

Effects of electric field training on the transport properties and photovoltaic properties of oxygen-deficient La0.8Sr0.2MnO3−δ films have been investigated. Oxygen-deficient films annealed in vacuum show obvious increase of resistance and photovoltaic effect, a direct correlation between the magnitude of the photovoltage and training electric field has been observed. The photovoltaic effect was remarkably enhanced by increasing the electrical pulse voltages, that is, it exhibits field-enhanced photovoltaic effect. The formation of Schottky like barrier at the Pt/La0.8Sr0.2MnO3−δ interface induced by oxygen vacancies accumulation is believed to be responsible for the increase of photovoltaic effect. These results may be important for practical applications in photoelectric devices.