Magnetoelectric properties of the multiferroic CuCrO$_2$ studied by means of ab initio calculations and Monte Carlo simulations

TL;DR

This study combines ab initio calculations and Monte Carlo simulations to explore the magnetic and ferroelectric properties of CuCrO$_2$, revealing its Néel temperature, magnetic ground state, and electric control of spin helicity, advancing understanding of multiferroicity in frustrated magnets.

Contribution

It provides a detailed theoretical analysis of CuCrO$_2$'s magnetoelectric properties, including exchange interactions, magnetic ground state, and electric control mechanisms, using first-principles and Monte Carlo methods.

Findings

Néel temperature estimated at ~27 K, close to experimental values.

Ground state identified as a proper-screw magnetic configuration.

Demonstrated electric control of spin helicity through hysteresis simulations.

Abstract

Motivated by the discovery of multiferroicity in the geometrically frustrated triangular antiferromagnet CuCrO$_2$ below its N\'eel temperature $T_N$, we investigate its magnetic and ferroelectric properties using ab initio calculations and Monte Carlo simulations. Exchange interactions up to the third nearest neighbors in the $ab$ plane, inter-layer interaction and single ion anisotropy constants in CuCrO$_2$ are estimated by series of density functional theory calculations. In particular, our results evidence a hard axis along the [110] direction due to the lattice distortion that takes place along this direction below $T_N$. Our Monte Carlo simulations indicate that the system possesses a N\'eel temperature $T_N\approx27$ K very close to the ones reported experimentally ($T_N = 24-26$ K). Also we show that the ground state is a proper-screw magnetic configuration with an incommensurate propagation vector pointing along the [110] direction. Moreover, our work reports the emergence of spin helicity below $T_N$ which leads to ferroelectricity in the extended inverse Dzyaloshinskii-Moriya model. We confirm the electric control of spin helicity by simulating $P$-$E$ hysteresis loops at various temperatures.