Coexistence of ferromagnetism and spin-orbit coupling by incorporation of platinum in two-dimensional VSe$_2$

TL;DR

This paper introduces a new 2D alloy V$_{1-x}$Pt$_x$Se$_2$ that exhibits both ferromagnetism and Rashba spin-orbit coupling, achieved by substituting platinum into VSe$_2$, enabling studies of their interplay at the 2D scale.

Contribution

It demonstrates experimentally and theoretically that platinum substitution in VSe$_2$ induces ferromagnetism and Rashba spin-orbit coupling in a 2D alloy, a novel combination for 2D materials.

Findings

Ferromagnetic order restored with Curie temperatures up to 25 K.

Presence of Rashba spin-orbit coupling due to platinum incorporation.

Homogeneous 2D alloy exhibits coexistence of ferromagnetism and spin-orbit effects.

Abstract

We report on a novel material, namely two-dimensional (2D) V$_{1-x}$Pt$_x$Se$_2$ alloy, exhibiting simultaneously ferromagnetic order and Rashba spin-orbit coupling. While ferromagnetism is absent in 1T-VSe$_2$ due to the competition with the charge density wave phase, we demonstrate theoretically and experimentally that the substitution of vanadium by platinum in VSe$_2$ (10-50 %) to form an homogeneous 2D alloy restores ferromagnetic order with Curie temperatures of 6 K for 5 monolayers and 25 K for one monolayer of V$_{0.65}$Pt$_{0.35}$Se$_2$. Moreover, the presence of platinum atoms gives rise to Rashba spin-orbit coupling in (V,Pt)Se$_2$ providing an original platform to study the interplay between ferromagnetism and spin-orbit coupling in the 2D limit.