Guangdong Provincial Key Laboratory of Magnetoelectric Physics and Devices, School of Physics, Sun Yat-sen University, Guangzhou 510275, China.
State Key Laboratory of Optoelectronic Materials and Technologies, School of Physics, Sun Yat-sen University, Guangzhou 510275, China.
ACS Appl Mater Interfaces. 2023 Mar 8;15(9):11983-11993. doi: 10.1021/acsami.2c20106. Epub 2023 Feb 21.
BiFeO, known as the "holy grail of all multiferroics", provides an appealing platform for exploration of multifield coupling physics and design of functional devices. Many fantastic properties of BiFeO are regulated by its ferroelastic domain structure. However, a facile programable control on the ferroelastic domain structure in BiFeO remains challenging and our understanding on the existing control strategies is also far from complete. This work reports a facile control of ferroelastic domain patterns in BiFeO thin films under area scanning poling by exploiting the tip bias as the control parameter. Combining scanning probe microscopy experiments and simulations, we found that BiFeO thin films with pristine 71° rhombohedral-phase stripe domains exhibit at least four switching pathways solely by controlling the scanning tip bias. As a result, one can readily write mesoscopic topological defects into the films without the necessity to change the tip motion. The correlation between conductance of the scanned region and the switching pathway is further investigated. Our results extend the current understanding on the domain switching kinetics and the coupled electronic transport properties in BiFeO thin films. The facile voltage control of ferroelastic domains should facilitate the development of configurable electronic and spintronic devices.
BiFeO 被称为“多铁性圣杯”，为探索多场耦合物理和设计功能器件提供了一个有吸引力的平台。BiFeO 的许多奇异性质受其铁弹畴结构的调节。然而，对 BiFeO 中铁弹畴结构的简便可编程控制仍然具有挑战性，我们对现有控制策略的理解也远不完整。本工作通过利用尖端偏压作为控制参数，在面积扫描极化下报告了对 BiFeO 薄膜中铁弹畴图案的简便控制。结合扫描探针显微镜实验和模拟，我们发现具有原始 71°菱面体相条纹畴的 BiFeO 薄膜仅通过控制扫描尖端偏压就至少有四种开关途径。因此，人们可以很容易地将介观拓扑缺陷写入薄膜中，而无需改变尖端运动。进一步研究了扫描区域的电导与开关途径之间的相关性。我们的结果扩展了对 BiFeO 薄膜中畴开关动力学和耦合电子输运性质的现有理解。铁弹畴的简便电压控制应该有助于可配置电子和自旋电子器件的发展。
