# Optical properties of Fe-Mn-Ga alloys

## TL;DR

This study combines first-principles calculations and experimental measurements to analyze the optical properties of Fe-Mn-Ga alloys, revealing good agreement and minimal impact of atomic and magnetic order on optical spectra.

## Contribution

It provides the first combined theoretical and experimental analysis of optical properties for Fe-Mn-Ga alloys with different atomic orders.

## Key findings

- Good agreement between calculated and experimental optical spectra.
- Atomic and magnetic order have minimal effect on optical properties.
- Both L2$_{1}$ and L1$_{2}$ phases show similar optical spectra.

## Abstract

The first-principles calculations of the electronic structures and the interband optical conductivity (OC) spectra have been performed for the stoichiometric Fe$_{2}$MnGa alloy with L2$_{1}$ and L1$_{2}$ types of atomic ordering. The calculated optical properties of Fe$_{2}$MnGa alloy for the L2$_{1}$ and L1$_{2}$ phases are complemented by the experimental OC spectra for bulk and thin film Fe-Mn-Ga alloy samples near the stoichiometry 2:1:1 with L2$_{1}$ and L1$_{2}$ (for bulks) as well as the body-centered-cubic and face-centered-cubic (for films) structures, respectively. A reasonable agreement between experimental and calculated interband OC spectra was obtained for both phases of the alloy. The experimental data show no significant difference in the OC spectra with respect to the degrees of atomic and magnetic orders of the samples.