Phase Transition and Magnetic Suppression in Heusler Alloy IrMnAl

TL;DR

This paper investigates the magnetic properties and pressure-induced phase transition of the IrMnAl Heusler alloy using first-principles calculations, revealing a structural change and insights into its weak ferromagnetism.

Contribution

It provides the first detailed computational analysis of pressure effects and phase transitions in IrMnAl, employing GGA+U to improve magnetic property predictions.

Findings

Structural phase transition at 5.6 GPa from cubic to tetragonal symmetry

Enhanced understanding of magnetic interactions and Curie temperature

Identification of weak ferromagnetism in the high-pressure phase

Abstract

This study conducts a comprehensive first-principles investigation of the IrMnAl Heusler alloy, highlighting its magnetic properties and assessing the effects of pressure-induced phase shift. The limitations of Generalized Gradient Approximation in accurately representing the compounds magnetic behavior is addressed by employing the GGA+U approach, which more effectively captures the electronic features. At 5.6 GPa pressure, we observe a novel structural phase transition from the cubic F4-3m to the P4-3m space group. The calculated Curie temperature, combined with the analysis of Mn-Mn exchange interaction, sheds light on the weak ferromagnetism observed in the new phase of the compound.