Optoelectronic and Ionic Effects on Transport in van der Waals Metal Selenophosphate <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline" overflow="scroll"><mml:msub><mml:mrow><mml:mi>Ag</mml:mi><mml:mi>Bi</mml:mi><mml:mi mathvariant="normal">P</mml:mi></mml:mrow><mml:mn>2</mml:mn></mml:msub><mml:msub><mml:mi>Se</mml:mi><mml:mn>6</mml:mn></mml:msub></mml:math>
Qiankun Li, Shun Wang, Jinshuo Xue, Ziwen Zhou, Yiqi Hu, Zhou Zhou, Zhijian Feng, Qingyu Yan, Yiqing Yu, Yuyan Weng, Rujun Tang, Xiaodong Su, Fengang Zheng, Liang Fang, Lü You
Abstract
Ionic migration in solid phases is actively explored as a mechanism for neuromorphic computing elements, for example, but direct imaging of the ionic migration and its correlation with macroscopic electronic transport are tricky. Through multiple state-of-the-art microscopy techniques the authors visualize Ag${}^{+}$ migration in AgBiP${}_{2}$Se${}_{6}$, and how it modulates the interfacial barrier to induce switchable diodelike transport in a device. Illuminating the device can be used to switch off its ionic tunability, expanding its functionality. These results provide direct insight into the mechanism of ion-mediated transport in ionically active semiconductors.