Defect-induced $4p$-magnetism in layered platinum diselenide

TL;DR

This paper investigates how layer thickness, defect density, and substrate influence defect-induced magnetism in PtSe₂ thin films, revealing strong inter-layer interactions that enable tuning magnetic properties for advanced device applications.

Contribution

It provides a theoretical analysis of the factors affecting defect-induced magnetism in PtSe₂, highlighting the role of inter-layer interactions and substrate effects for the first time.

Findings

Magnetism in PtSe₂ is highly sensitive to layer thickness and defect density.

Inter-layer interactions significantly influence magnetic coupling and moments.

Substrate choice can dramatically alter magnetic properties.

Abstract

Platinum diselenide (PtSe$_{2}$) is a recently-discovered extrinsic magnet, with its magnetism attributed to the presence of Pt-vacancies. The host material to these defects itself displays interesting structural and electronic properties, some of which stem from an unusually strong interaction between its layers. To date, it is not clear how the unique intrinsic properties of PtSe$_2$ will affect its induced magnetism. In this theoretical work, we show that the defect-induced magnetism in PtSe$_{2}$ thin films is highly sensitive to: (i) the layer-thickness (ii) defect density, and (iii) substrate choice. These different factors dramatically modify all magnetic properties, including the magnitude of local moments, strength of the coupling, and even nature of the coupling between the moments. We further show that the strong inter-layer interactions are key to understanding these effects. A better understanding of the various influences on magnetism, can enable controllable tuning of the magnetic properties in Pt-based dichalcogenides, which can be used to design novel devices for magnetoelectric and magneto-optic applications.