多铁材料BiFeO3不但具有优越的铁电特性,同时由于电、磁、光之间的耦合作用,可以实现电场控制磁化,光照控制电学性质,是研究新型多参量耦合器件的首选材料。文章介绍了作者实验室对铁电材料BiFeO3异质结构的可反转二极管效应和电致电阻效应的研究。在理论研究方面,作者考虑了金属电极的不完全屏蔽效应,提出了极化控制界面肖特基势垒高度模型,解释了金属/铁电结构/金属的可反转二极管效应。在BiFeO3/La0.7Sr0.3MnO3铁电/铁磁异质结构实验研究方面,作者研究了BiFeO3薄膜厚度对体系电学和磁学性质的影响,实现了在光、电双场调控下研究Au/BiFeO3/La0.7Sr0.3MnO3/SrTiO3体系的光、电性质,可为以后研究多参量对器件性能的影响提供参考。
The resistive switching and switchable diode effects in BiFeO3 heterostructures have been investigated. A self-consistent numerical model, which includes the incomplete screening effect of metal electrodes, has been developed to reveal the mechanism of the switchable diode be-havior in metal-ferroelectric-metal structures. Experimental studies have been conducted on the ef-fect of the BiFeO3 film thickness on the electric and magnetic properties of the BiFeO3/La0.7Sr0.3MnO3 heterostructure, as well as the resistive switching effect and photoelectric behavior in Au/BiFeO3/La0.7Sr0.3MnO3/SrTiO3 heterostructures under electro-photo dual modulation. Our results should open a way for potential applications through combining multiple degrees of freedom in devices.