Exchange striction driven magnetodielectric effect and potential photovoltaic effect in polar CaOFeS

TL;DR

This study reveals that CaOFeS exhibits a magnetodielectric effect driven by exchange striction and has strong visible light absorption, making it promising for photovoltaic applications.

Contribution

It provides a comprehensive theoretical analysis of CaOFeS's magnetic, electronic, and optical properties, highlighting its potential for magnetodielectric and photovoltaic applications.

Findings

CaOFeS has an Ising-like G-type antiferromagnetic ground state.

The material exhibits a significant magnetodielectric effect due to exchange striction.

It has a high light-to-electricity conversion efficiency of up to 24.2%.

Abstract

CaOFeS is a semiconducting oxysulfide with polar layered triangular structure. Here a comprehensive theoretical study has been performed to reveal its physical properties, including magnetism, electronic structure, phase transition, magnetodielectric effect, as well as optical absorption. Our calculations confirm the Ising-like G-type antiferromagnetic ground state driven by the next-nearest neighbor exchanges, which breaks the trigonal symmetry and is responsible for the magnetodielectric effect driven by exchange striction. In addition, a large coefficient of visible light absorption is predicted, which leads to promising photovoltaic effect with the maximum light-to-electricity energy conversion efficiency up to 24.2%.