中文摘要：

作为一种显著的多铁性材料,由于Bi FeO3的禁带宽度位于可见光波段,近年来它独特的光学性质（例如,可翻转的光伏效应、不同于传统材料的大于禁带宽度的光生电压、光致伸缩效应等）格外引人关注。作者将一束能量大于材料禁带宽度的激光引入原子力显微镜中,利用开尔文力显微技术,测量到不同电畴结构的表面电势差长时间衰减后的光致恢复效应。这种光致电势恢复可以理解为被拉到表面的光生载流子导致的表面电荷重新分布的结果。这一结果展现了一种新的铁电性材料的光学特性,并提供了一种把光学性质应用于非破坏性读取铁电存储信号的新思路。

英文摘要：

By combining piezoelectric force microscopy with scanning surface potential microscopy and introducing a laser beam. we have demonstrated that the surface poicntial contrast of BiFeO3 films can be recovered by light illumination. The recovering mechanism is under- stood based on the redistribution of the photo-induced charges driven by the internal electric field. Furthermore, we have created a 12-cell memory pattern based on a BiFeO3 film to show the feasi- bility of such photo-assisted non-volatile and non-destructive readout of the ferroelectric memory. Keywords photoelectricity coupled with fcrroelectricity, non-destructive information readout, photo-recovered surface potential contrast, sell-consistent numerical calculation