# Low damping magnetic properties and perpendicular magnetic anisotropy with strong volume contribution in the Heusler alloy Fe1.5CoGe

## TL;DR

This study investigates the magnetic damping and perpendicular magnetic anisotropy in Fe1.5CoGe Heusler alloy thin films, revealing low damping, strong volume anisotropy, and interfacial effects influenced by annealing.

## Contribution

It demonstrates significant volume contribution to perpendicular anisotropy and low damping in Fe1.5CoGe, contrasting with typical Heusler alloys, and explores annealing effects on interfacial anisotropy.

## Key findings

- Lowest damping value of α=2.18×10^{-3} achieved.
- Large volume anisotropy of (4.3±0.5)×10^5 J/m^3 observed.
- Interfacial anisotropy varies with annealing temperature.

## Abstract

We present a study of the dynamic magnetic properties of TiN-buffered epitaxial thin films of the Heusler alloy Fe$_{1.5}$CoGe. Thickness series annealed at different temperatures are prepared and the magnetic damping is measured, a lowest value of $\alpha=2.18\times 10^{-3}$ is obtained. The perpendicular magnetic anisotropy properties in Fe$_{1.5}$CoGe/MgO are also characterized. The evolution of the interfacial perpendicular anisotropy constant $K^{\perp}_{\rm S}$ with the annealing temperature is shown and compared with the widely used CoFeB/MgO interface. A large volume contribution to the perpendicular anisotropy of $(4.3\pm0.5)\times 10^{5}$ $\rm J/m^3$ is also found, in contrast with vanishing bulk contribution in common Co- and Fe-based Heusler alloys.