Influences of leakage currents on the transport properties and photoelectric effects in heterojunctions composed of colossal magnetoresistance manganites and Nb-doped titanates

摘要

The effects of leakage currents were investigated for Pr 0.7Sr 0.3MnO 3/Nb-SrTiO 3 heterojunctions. It was found that small amounts of leakage currents could cause pronounced detriment to the rectifying properties but had very limited impacts on the barrier heights determined from the forward currents. Significant open circuit voltages V OC were observed when the highly rectified junctions were illuminated by a visible light with a wavelength of 532 nm. For the less rectified junctions, the leakage currents reduced V OC severely and resulted in an anomalous temperature dependence of V OC. Theories for semiconductor contacts were employed in order to discuss these results. © 2012 American Institute of Physics.