Giant Anisotropic Magnetoresistance in Magnetic Monolayers CrPX3 (X = S, Se, Te) due to symmetry breaking between the in-plane and out-of-plane crystallographic axes

TL;DR

This study reveals that magnetic monolayers CrPX3 exhibit large, tunable anisotropic magnetoresistance due to symmetry-breaking effects, with potential applications in advanced 2D spintronic devices.

Contribution

We demonstrate significant AMR in 2D CrPX3 monolayers driven by magnetization-dependent spin-orbit coupling, enhanced by atomic number and strain, which is a novel insight for 2D spintronics.

Findings

AMR reaches up to 150% in CrPTe3.

AMR can be doubled with 4% biaxial strain.

AMR is driven by magnetization-dependent spin-orbit coupling.

Abstract

Anisotropic magnetoresistance (AMR) has a crucial feature for developing highly sensitive sensors and innovative memory devices. While extensively studied in bulk materials, AMR effects in these materials are typically weak. Recent advancements indicate that two-dimensional (2D) van der Waals magnetic materials possess unique magnetic properties, potentially including significant AMR characteristics. In this study, we utilize density functional theory and the Boltzmann transport equation to investigate AMR in magnetic monolayers CrPX3 (X = S, Se, Te). Our findings reveal a substantially large AMR in these 2D magnetic compounds. This enhancement is attributed to magnetization (M)-dependent spin-orbit coupling (SOC), arising from the broken symmetry between in-plane and out-of-plane orientations. This results in significant M-dependent band splitting and subsequent variations in electron velocity. Additionally, we find that the M-dependent SOC is significantly enhanced by increasing the atomic number of the chalcogen X in CrPX3, achieving an exceptional 150% AMR in CrPTe3. Furthermore, our study demonstrates that AMR can be effectively modulated by applying biaxial strain, resulting in a twofold increase with a 4% strain. These findings propose a novel approach to enhancing 2D-based AMR spintronic devices, making a substantial contribution to the field.