Spin-glass state induced by Mn-doping into a moderate gap layered semiconductor SnSe$_2$

TL;DR

This study demonstrates that Mn-doping in SnSe$_2$ induces a spin-glass state due to competing magnetic interactions, revealing new magnetic phenomena in layered semiconductors.

Contribution

It reports the successful synthesis and magnetic characterization of Mn-doped SnSe$_2$, showing the emergence of a spin-glass state and elucidating the origin of ferromagnetism via ab initio calculations.

Findings

Spin-glass behavior appears below ~60 K.

Coexistence of ferromagnetic and antiferromagnetic interactions.

Ferromagnetism originates from Mn 3d electrons.

Abstract

Various types of magnetism can appear in emerging quantum materials such as van der Waals layered ones. Here, we report the successful doping of manganese atoms into a post-transition metal dichalcogenide semiconductor: SnSe$_2$. We synthesized a single crystal Sn$_{1-x}$Mn$_x$Se$_{2}$ with $\textit{x}$ = 0.04 by the chemical vapor transport (CVT) method and characterized it by x-ray diffraction (XRD) and energy-dispersive x-ray spectroscopy (EDS). The magnetic properties indicated a competition between coexisting ferromagnetic and antiferromagnetic interactions, from the temperature dependence of the magnetization, together with magnetic hysteresis loops. This means that magnetic clusters having ferromagnetic interaction within a cluster form and the short-range antiferromagnetic interaction works between the clusters; a spin-glass state appears below ~ 60 K. Furthermore, we confirmed by $\textit{ab initio}$ calculations that the ferromagnetic interaction comes from the 3$\textit{d}$ electrons of the manganese dopant. Our results offer a new material platform to understand and utilize the magnetism in the van der Waals layered materials.