Resistance switching and white-light photovoltaic effects in BiFeO3/Nb-SrTiO3 heterojunctions

BiFeO3/Nb-SrTiO3 heterojunctions with room-temperature resistance switching (RS) and white-light photovoltaic (PV) effects were fabricated by pulsed laser deposition. The current-voltage characteristics of these heterojunctions show a good rectifying property with a large rectifying ratio of 10(4). Nonvolatile bipolar RS effect was observed with an ON/OFF-state current ratio of about 10(2). The heterojunctions also exhibit a substantial white-light PV effect. Both the RS and PV behaviors can be modulated by additional pulsed voltages, which control the electric polarization of the heterojunctions. This letter is helpful for exploring the multifunctional heterojunctions and their applications in memory devices and solar cells. (C) 2011 American Institute of Physics. [doi:10.1063/1.3584031]