Very large magnetoresistance in Fe$_{0.28}$TaS$_{2}$ single crystals

TL;DR

This study reports extremely large magnetoresistance in Fe$_{0.28}$TaS$_{2}$ single crystals, driven by spin disorder scattering in a strong spin-orbit coupling environment, revealing potential for designing high MR materials.

Contribution

It demonstrates a record-high magnetoresistance in Fe$_{0.28}$TaS$_{2}$, highlighting the role of spin disorder scattering and strong spin-orbit coupling as a design principle for large MR materials.

Findings

Magnetoresistance exceeds 60% at 2 K in Fe$_{0.28}$TaS$_{2}$

MR is nearly 100 times higher than in Fe$_{0.25}$TaS$_{2}$

Large MR attributed to spin disorder scattering in strong spin-orbit coupling environment

Abstract

Magnetic moments intercalated into layered transition metal dichalcogenides are an excellent system for investigating the rich physics associated with magnetic ordering in a strongly anisotropic, strong spin-orbit coupling environment. We examine electronic transport and magnetization in Fe$_{0.28}$TaS$_{2}$, a highly anisotropic ferromagnet with a Curie temperature $T_{\mathrm{C}} \sim 68.8~$K. We find anomalous Hall data confirming a dominance of spin-orbit coupling in the magnetotransport properties of this material, and a remarkably large field-perpendicular-to-plane MR exceeding 60% at 2 K, much larger than the typical MR for bulk metals, and comparable to state-of-the-art GMR in thin film heterostructures, and smaller only than CMR in Mn perovskites or high mobility semiconductors. Even within the Fe$_x$TaS$_2$ series, for the current $x$ = 0.28 single crystals the MR is nearly $100\times$ higher than that found previously in the commensurate compound Fe$_{0.25}$TaS$_{2}$. After considering alternatives, we argue that the large MR arises from spin disorder scattering in the strong spin-orbit coupling environment, and suggest that this can be a design principle for materials with large MR.