Discovery of Robust Ferroelectricity in 2D Defective Semiconductor α‑Ga2Se3
Discovery of Robust Ferroelectricity in 2D Defective Semiconductor α‑Ga2Se3
复制标题
二维缺陷半导体αGa 2 Se 3 中鲁棒铁电性的发现
DOI：
10.1002/smll.202105599
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发表时间：
2021
期刊：
影响因子：
13.3
通讯作者：
Xiaohong Xu
中科院分区：
文献类型：
--
作者：
Wuhong Xue;Qitao Jiang;Fakun Wang;Ri He;Ruixue Pang;Huali Yang;Peng Wang;Ruilong Yang;Zhicheng Zhong;Tianyou Zhai;Xiaohong Xu
2D ferroelectrics with robust polar order in the atomic‐scale thickness at room temperature are needed to miniaturize ferroelectric devices and tackle challenges imposed by traditional ferroelectrics. These materials usually have polar point group structure regarding as a prerequisite of ferroelectricity. Yet, to introduce polar structure into otherwise nonpolar 2D materials for producing ferroelectricity remains a challenge. Here, by combining first‐principles calculations and experimental studies, it is reported that the native Ga vacancy‐defects located in the asymmetrical sites in cubic defective semiconductor α‑Ga2Se3can induce polar structure. Meanwhile, the induced polarization can be switched in a moderate energy barrier. The switched polarization is observed in 2D α‑Ga2Se3nanoflakes of ≈4 nm with a high switching temperature up to 450 K. Such polarization switching could arise from the displacement of Ga vacancy between neighboring asymmetrical sites by applying an electric field. This work removes the point group limit for ferroelectricity, expanding the range of 2D ferroelectrics into the native defective semiconductors.
