Two-Dimensional VSi2X2N2 (X = P, As, Sb, Bi) Janus Monolayers: Spin-Polarized Electronic Structure and Perpendicular Magnetic Anisotropy

The discovery of ferromagnetic two-dimensional (2D) materials provides reference value for the exploration low-dimensional magnetism and new spintronic devices. VSi2N4 monolayer is with half-metallic characteristics, which a 2D material in field spintronics. Here, electronic structure magnetic anisotropy VSi2X2N2 (X = P, As, Sb, Bi) Janus monolayers are studied systematically via first-principles calculations. results show that VSi2P2N2, VSi2As2N2 VSi2Bi2N2 magnetic, but VSi2Sb2N2 nonmagnetic. At X As Bi, metallic ferromagnetic. VSi2P2N2 in-plane anisotropy, while shows perpendicular (PMA). tensile strain increases, spin-down energy band gradually moves up spin-up channel down. ε +12%, shifts above Fermi level, showing characteristic gap 0.775 eV calculated using Perdew–Burke–Ernzerhof (PBE) exchange–correlation function. moment induced at an electric −0.4 V/Å +0.2 V/Å, where PMA appears. These data provide basic theoretical guidance development