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The short-circuit photocurrent (ISC) that can be reversed by polarization switch enhances with temperature increasing to 130 °C in the epitaxial BiFeO3 thin film on SrTiO3 substrate. The La2/3Sr1/3MnO3/BiFeO3/indium tin oxide (In2O3:SnO2 = 9:1) junction shows the current rectifying characteristic and the photovoltaic effect at 20–130 °C. Importantly, the ISC can be reversed by the polarization switch in this temperature range. More charge carriers are activated and the density of free electrons enhances with the increase in the temperature, which results in the decrease in the depletion layer width. As a result, the open-circuit voltage decreases 50% and the ISC increases from 180 nA to 404 nA with the increase in the temperature from 20 °C to 130 °C. This suggests that the corresponding sensors and devices can be used at a relatively high temperature.

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Sr 2 FeMoO 6 ceramics with different Fe/Mo antisite defect (ASD) concentrations and grain-boundary (GB) properties were prepared. The competitive and combining effects of GB and Fe/Mo ASD on the transport and magnetoresistance were discussed. The GB properties, that is, intergrain coupling strength, positively related with resistivity value, is extremely sensitive to the total flux of reducing gas, in general, lower total gas flux leads to larger resistivity, thus stronger intergrain coupling strength, and then the contributions of GB effect to low-field magnetoresistance (LFMR) increase appreciably regardless of the amount of ASD. In detail, when ASD concentration is less than 26%, LFMR is dominantly controlled by the GB effect. However, the suppressed ASD effect on LFMR behavior comes to play when the ASD content is larger than or equal to 26%, where the GB and ASD effects contribute together to the LFMR. R. French-contributing editor Manuscript No. 33053. J ournalthe suppressed ASD effect on LFMR comes to play when ASD content is larger than or equal to 26%, where both GB effect and ASD effect contribute to LFMR behavior.

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