Electronic Structure Calculations of Magnetic Exchange Interactions in Europium Monochalcogenides

TL;DR

This paper uses advanced computational methods to study magnetic exchange interactions in europium monochalcogenides, reproducing experimental results and exploring pressure effects and ways to enhance magnetic transition temperatures.

Contribution

It introduces a combined local spin density and Hubbard 1 approach to accurately model exchange interactions in EuX compounds, revealing pressure-induced competition affecting magnetic properties.

Findings

Reproduces experimental bulk modulus and critical pressure data.

Identifies pressure-induced competition between exchange mechanisms.

Discusses potential methods to increase T_c in EuX materials.

Abstract

Using a combination of local spin density and Hubbard 1 approximations we study the mechansim of exchange interacion in EuX (X=O, S, Se and Te). We reproduce known experimental results about bulk modulus, critical pressure for structural phase transition, magnetic ordering temperature, spin--wave dispersions as well as momentum-- and tempearuture--dependent band shift. Our numerical results show pressure induced competition between the hybirization enhanced exchange interaction and Kondo--like coupling in EuO. Possible ways to enhance T_{c} are discussed.