Electric Field Effects on Photoconductivity and Photoluminescence in MAPbI$_{\mathrm{3}}$ Perovskite

The origin of ``hysteresis behavior'' in I-V response of MAPbI$_{\mathrm{3}}$ perovskite devices is still under debate. We characterized this electric field induced hysteresis by monitoring the changes of photoconductivity (E-PC) and photoluminescence (E-PL) from the MAPbI$_{\mathrm{3}}$ film deposited on inter-digital electrodes. Interestingly, we observed a ``sign change'' in both E-PC and E-PL effects, depending on the applied field and temperature. The E-PC/E-PL could be ``frozen'' when cooling the device under external field to lower temperature. These results reveal multiple possible reasons for the intrinsic hysteresis behavior in MAPbI$_{\mathrm{3}}$ perovskite devices. This work was supported by the Utah NSF-MRSEC program DMR 1121252.