Electric-Field-Induced Room-Temperature Antiferroelectric-Ferroelectric Phase Transition in van der Waals Layered GeSe

作者：Guan, Zhao; Zhao, Yifeng; Wang, Xiaoting; Zhong, Ni^*; Deng, Xing; Zheng, Yunzhe; Wang, Jinjin; Xu, Dongdong; Ma, Ruru; Yue, Fangyu; Cheng, Yan; Huang, Rong; Xiang, Pinghua; Wei, Zhongming^*; Chu, Junhao; Duan, Chungang^*

来源：ACS Nano, 2022, 16(1): 1308-1317.

DOI：10.1021/acsnano.1c09183

• antiferroelectric
• two-dimensional ferroelectrics
• GeSe
• antiferroelectric-ferroelectric phase transition
• electric field

Searching van der Waals ferroic materials that can work under ambient conditions is of critical importance for developing ferroic devices at the two-dimensional limit. Here we report the experimental discovery of electric-field-induced reversible antiferroelectric (AFE) to ferroelectric (FE) transition at room temperature in van der Waals layered alpha-GeSe, employing Raman spectroscopy, transmission electron microscopy, second-harmonic generation, and piezoelectric force microscopy consolidated by first-principles calculations. An orientationdependent AFE-FE transition provides strong evidence that the in-plane (IP) polarization vector aligns along the armchair rather than zigzag direction in alpha-GeSe. In addition, temperature-dependent Raman spectra showed that the IP polarization could sustain up to higher than 700 K. Our findings suggest that alpha-GeSe, which is also a potential ferrovalley material, could be a robust building block for creating artificial 2D multiferroics at room temperature.

• 单位
  中国科学院