Magnetic Properties of NbSi2N4, VSi2N4, and VSi2P4 Monolayers

TL;DR

This paper investigates the magnetic properties of NbSi2N4, VSi2N4, and VSi2P4 monolayers, revealing their potential for spintronic applications due to their ferromagnetism and tunable magnetic orientations at room temperature.

Contribution

It reports the magnetic characteristics and tunability of these novel 2D materials, expanding the family of stable, air-resistant ferromagnetic monolayers.

Findings

VSi2P4 and VSi2N4 have Curie temperatures above room temperature.

Magnetic moments in VSi2N4 can be switched by strain or doping.

These materials are easy-plane ferromagnets with negligible in-plane anisotropy.

Abstract

The recent demonstration of MoSi2N4 and its exceptional stability to air, water, acid, and heat has generated intense interest in this family of two-dimensional (2D) materials. Among these materials, NbSi2N4, VSi2N4, and VSi2P4 are semiconducting, easy-plane ferromagnets with negligible in-plane magnetic anisotropy. They thus satisfy a necessary condition for exhibiting a dissipationless spin superfluid mode. The Curie temperatures of monolayer VSi2P4 and VSi2N4 are determined to be above room temperature based on Monte Carlo and density functional theory calculations. The magnetic moments of VSi2N4 can be switched from in-plane to out-of-plane by applying tensile biaxial strain or electron doping.