Photoconductivity in BiFeO 3/La 0.7Sr 0.3MnO 3 heterostructure

Abstract

In this letter, an oxide heterostructure has been fabricated by successively growing La 0.7Sr 0.3MnO 3 (LSMO) and BiFeO 3 (BFO) layers on LaAlO 3 (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 BiFeO 3/La 0.7Sr 0.3MnO 3 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 BiFeO 3/La 0.7Sr 0.3MnO 3 film under illumination from 160 mW/cm 2 and 200 mW/cm 2 green-light source, and photoconductivities increase with the intensity of light enhanced.