Physical Sciences and Engineering Division, King Abdullah University of Science and Technology , Thuwal, Jeddah 23955-6900, Kingdom of Saudi Arabia.
Shenyang National Laboratory for Materials Science, Institute of Metal Research (IMR), Chinese Academy of Sciences (CAS) , Shenyang 110016, China.
Nano Lett. 2018 Feb 14;18(2):1253-1258. doi: 10.1021/acs.nanolett.7b04852. Epub 2018 Feb 5.
Enriching the functionality of ferroelectric materials with visible-light sensitivity and multiaxial switching capability would open up new opportunities for their applications in advanced information storage with diverse signal manipulation functions. We report experimental observations of robust intralayer ferroelectricity in two-dimensional (2D) van der Waals layered α-InSe ultrathin flakes at room temperature. Distinct from other 2D and conventional ferroelectrics, InSe exhibits intrinsically intercorrelated out-of-plane and in-plane polarization, where the reversal of the out-of-plane polarization by a vertical electric field also induces the rotation of the in-plane polarization. On the basis of the in-plane switchable diode effect and the narrow bandgap (∼1.3 eV) of ferroelectric InSe, a prototypical nonvolatile memory device, which can be manipulated both by electric field and visible light illumination, is demonstrated for advancing data storage technologies.
赋予铁电材料可见光敏感性和多轴切换能力，可以为其在具有多种信号处理功能的先进信息存储中的应用开辟新的机会。我们报告了在室温下二维（2D）范德华层状α-InSe 超薄薄片中观察到的稳健的层内铁电性的实验结果。与其他二维和传统铁电体不同，InSe 表现出固有相互关联的面外和面内极化，其中垂直电场反转面外极化也会引起面内极化的旋转。基于面内可切换二极管效应和铁电 InSe 的窄带隙（约 1.3 eV），演示了一种典型的非易失性存储器件，它可以通过电场和可见光照射来控制，用于推进数据存储技术。
