The effects of competing magnetic interactions on the electronic properties of CuCrS2 and CuCrSe2

TL;DR

This study investigates how competing magnetic interactions influence the electronic and magnetic properties of layered CuCrS2 and CuCrSe2, revealing differences in magnetic order and excitations due to their electronic structures.

Contribution

It provides a detailed comparison of magnetic and electronic behaviors in CuCrS2 and CuCrSe2, highlighting the role of competing interactions in magnetic order suppression.

Findings

CuCrS2 exhibits 3D magnetic order with a sharp transition at 40K.

CuCrSe2 shows no long-range order, indicating a 2D spin-liquid-like state.

The magnetic behavior is explained by competition between intra-layer and inter-layer interactions.

Abstract

We present a detail study of the electrical resistivity, thermoelectric power, magnetic susceptibility \c{hi} and the heat capacity CP in antiferromagnetic layered compounds CuCrS2 and CuCrSe2 at 2K-300K. CuCrS2 showed sharp cusp in \c{hi} and a lambda-like peak in CP at TN = 40K as expected for a 3D- magnetic order, while more metallic CuCrSe2 showed a rounded maximum in \c{hi} and the absence of sharp peak in CP around 55K, the CP at low temperature has T2-dependence in it which suggests the absence of the long range order and 2D spin-liquid like excitation in its magnetic phase. We explain the absence of the magnetic order in the selenide compound as resulting from the effective competition of the magnetic interactions from the distant neighbors; the indirect exchange among the intra-layer Cr-atoms increases in more metallic selenide compound which competes with the direct antiferromagnetic interactions between the Cr-atoms of different layers which destroys the long range magnetic order.