中国物理B ›› 2023, Vol. 32 ›› Issue (3): 37104-037104.doi: 10.1088/1674-1056/acae7b
Ming Yan(闫明)1, Zhi-Yuan Xie(谢志远)2,†, and Miao Gao(高淼)3,‡
Ming Yan(闫明)1, Zhi-Yuan Xie(谢志远)2,†, and Miao Gao(高淼)3,‡
摘要: Two-dimensional (2D) magnetic materials have attracted tremendous research interest because of the promising application in the next-generation microelectronic devices. Here, by the first-principles calculations, we propose a two-dimensional ferromagnetic material with high Curie temperature, manganese tetranitride MnN4 monolayer, which is a square-planar lattice made up of only one layer of atoms. The structure is demonstrated to be stable by the phonon spectra and the molecular dynamic simulations, and the stability is ascribed to the π-d conjugation between π orbital of N=N bond and d orbital of Mn. More interestingly, the MnN4 monolayer displays robust 2D ferromagnetism, which originates from the strong exchange couplings between Mn atoms due to the π-d conjugation. The high critical temperature of 247 K is determined by solving the Heisenberg model using the Monte Carlo method.
中图分类号: (Density functional theory, local density approximation, gradient and other corrections)