Author(s): Liu, C (Liu, Chang); Guan, S (Guan, Shan); Yin, HB (Yin, Huabing); Wan, WH (Wan, Wenhui); Wang, YX (Wang, Yuanxu); Zhang, Y (Zhang, Ying)

Source: APPLIED PHYSICS LETTERS Volume: 115 Issue: 25 Article Number: 252904 DOI: 10.1063/1.5133022 Published: DEC 16 2019

Abstract: Two-dimensional (2D) ferroelectricity and ferromagnetism have attracted a lot of attention due to their promising applications, but 2D materials with both properties are quite rare. Here, by performing first-principles calculations, we propose that monolayer gamma-GeSe is a 2D ferroelectric material with an out-of-plane polarization of about 6.48 x 10(-12) C/m. It has a Mexican-hat-like band structure, leading to itinerant ferromagnetism upon hole doping. This ferromagnetic phase transition occurs when the doping concentration is about 7.4 x 10(12)/cm(2), and the ferromagnetism can be maintained near 880 K when increasing the doping concentration. Both the ferroelectricity and the induced ferromagnetism can be well modulated by strain. These features make gamma-GeSe a promising material for making microelectronics and spintronics devices. Our work also paves the way for searching long-sought high temperature 2D multiferroics.

Accession Number: WOS:000505535900030

ISSN: 0003-6951

eISSN: 1077-3118

Full Text: https://aip.scitation.org/doi/10.1063/1.5133022