Intrinsic Multiferroic in VNI Monolayer

Abstract

Two-dimensional (2D) multiferroic materials, exhibiting both ferromagnetism and ferroelasticity, have promising applications in the miniaturization of quantum devices, such as high-density data storage and spintronic devices. Using firstprinciples calculations, we propose a 2D material, a ternary, vanadium−nitride−halide compound VNI. Its dynamic, mechanical, and thermal stabilities are confirmed by phonon spectrum, elastic modulus, and molecular dynamics simulations. The VNI monolayer is a robust ferromagnetic metal with a sizable in-plane magnetic anisotropic energy (153 μeV per V atom). Meanwhile, the monolayer has a moderate ferroelastic switching barrier of 100.66 meV/atom, which would facilitate the fast ferroelastic dynamics under external stress. Notably, the magnetic anisotropy axis of the VNI monolayer can be adjusted from the a-axis to the baxis through reversible ferroelastic strain, exhibiting the characteristics of magnetoelastic coupling. These results shed light on the design of nonvolatile-memory devices.

Two-dimensional ferroelastic and ferromagnetic NiOX (X = Cl and Br) with half-metallicity and a high Curie temperature

“…The reversible ferroelastic strain is estimated to be 16.7% and 16.3% for NiOCl and NiOBr, respectively. The evaluated values are comparable to those of BP 5 (41.4%) 53 and phosphorene (37.9%), 54 and are close to those of GeS (17.8%), 54 InOCl (17.7%), 58 and VNI (17.6%), 59 implying a strong switching signal in the NiOCl and NiOBr monolayers. We note that the energy difference between the transition state and the initial state obtained by NEB calculations is consistent with that of the previous calculations in Fig.…”

Novel two-dimensional ferromagnetic materials CrX2 (X = O, S, Se) with high Curie temperature

“…The reversible ferroelastic strain is calculated to be 38.7% and 42.2% for CrS 2 and CrSe 2 monolayers, respectively, which are comparable to that of BP 5 (41.4%), 72 phosphorene (37.9%), 73 CrSCl (36.5%), and CrSBr (31.5%) monolayers, 52 but larger than those of most 2D ferroelastic materials, such as FeO 2 H(23.5%), 77 Nb 2 GeTe 4 (22.1%), and Nb 2 SiTe 4 (24.4%), 78 and VNI (17.6%). 79 Hence, CrS 2 and CrSe 2 monolayers have ultrahigh reversible strain.…”

Predicted novel two-dimensional ferromagnetic VO2 with high Curie temperature and ferroelasticity

“…[1][2][3][4][5] Since the discovery of ferromagnetism in 2D Cr 2 Ge 2 Te 6 6 and CrI 3 , 7 a great deal of scientific effort has been devoted to the study of 2D magnetic materials both experimentally and theoretically. [8][9][10][11][12][13][14] However, despite a tidal wave of theoretical predictions and experimental studies claiming to find versatile and high Curie temperature (T C ) 2D magnetic materials, the scarcity and rather low T C of 2D intrinsic ferromagnets 1 are the fundamental obstacles to their practical applications in spintronics. Further exploration of 2D multifunctional magnetic materials at high Curie temperatures is urgent.…”