Anomalous Hall effect in two-dimensional non-collinear antiferromagnetic semiconductor Cr0.68Se

TL;DR

This study reports the discovery of anomalous Hall effect and large negative magnetoresistance in 2D non-collinear antiferromagnetic Cr0.68Se, revealing insights into its magnetic and transport properties with potential applications.

Contribution

It is the first detailed investigation of magnetic and transport properties, including AHE and MR, in 2D non-collinear antiferromagnetic Cr0.68Se semiconductors.

Findings

Cr0.68Se exhibits non-collinear AFM behavior with TN=42 K.

It shows a significant AHE and negative MR below TN.

The AHE is mainly due to skew-scattering mechanism.

Abstract

Cr0.68Se single crystals with two-dimensional (2D) character have been grown, and the detailed magnetization M(T), electrical transport properties (including longitudinal resistivity and Hall resistivity and thermal transport ones (including heat capacity Cp(T) and thermoelectric power (TEP) S(T)) have been measured. There are some interesting phenomena: (i) Cr0.68Se presents a non-collinear antiferromagnetic (AFM) semiconducting behavior with the Neel temperature TN = 42 K and the activated energy Eg=3.9 meV; (ii) It exhibits the anomalous Hall effect (AHE) below TN and large negative magnetoresistance (MR) about 83.7% (2 K, 8.5 T). The AHE coefficient RS is 0.385 cm-3/C at T=2 K and the AHE conductivity {\sigma}H is about 1 ohm-1cm-1 at T=40 K, respectively; (iii) The scaling behavior between the anomalous Hall resistivity and the longitudinal resistivity is linear and further analysis implies that the origin of the AHE in Cr0.68Se is dominated by the skew-scattering mechanism. Our results may be helpful for exploring the potential application of these kind of 2D AFM semiconductors.