Effects of -ray irradiation on ferroelectric properties of Pr and Mn co-substituted BiFeO3 thin films

Effects of -ray irradiation on ferroelectric properties of Pr and Mn co-substituted BiFeO3 thin films Zheng Wen, Di Wu, Jiating Zhu, and Aidong Li National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093, China and Department of Materials Science and Engineering, College of Engineering and Applied Sciences, Nanjing University, Nanjing 210093, China College of Physical Science, Qingdao University, Qingdao 266071, China Institute for Application of Atomic Energy, Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China Abstract -ray irradiation effects on ferroelectric properties of (Bi0.85Pr0.15)(Fe0.95Mn0.05)O3 (BPFMO) thin films are investigated by pizeoresponse force microscopy and polarization-voltage hysteresis measurements. The irradiated BPFMO thin-film capacitors show reduced polarizations and imprinted hysteresis loops. The loss of nonvolatile polarization increases with the decrease of polarization values prior to the irradiation and the imprint of hysteresis loops depends on the direction of polarization. These are discussed in terms of separation of -ray-excited electron-hole pairs by the depolarization field and subsequent charge trapping and aggregation on charged domain walls in BPFMO thin films.