Photoconductivity in BiFeO3/La0.7Sr0.3MnO3 heterostructure

In this letter, an oxide heterostructure has been fabricated by successively growing La0.7Sr0.3MnO3 (LSMO) and BiFeO3 (BFO) layers on LaAlO3 (100) by pulsed laser deposition. Analysis of the leakage current at different temperature demonstrated that the Poole–Frenkel dominated the leakage current mechanism. Additionally, the BiFeO3/La0.7Sr0.3MnO3 heterostructure exhibits a positive colossal magnetoresistance (MR) effect over a temperature range of 50–320 K. The maximum MR values are determined to be about 45.32% at H = 0.5 T and 28.34% at H = 0.3 T. At last, we report photoconductivity in BiFeO3/La0.7Sr0.3MnO3 film under illumination from 160 mW/cm2 and 200 mW/cm2 green-light source, and photoconductivities increase with the intensity of light enhanced.