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arXiv · 2202.05997

Terahertz magneto-optical response in ferromagnetic Fe-Co-Al alloys

Ming Lei·Sinisa Coh
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Abstract

We study the magneto-optical properties of Fe-Co-Al ordered alloys in the terahertz range of frequencies. Using the standard Kubo-based approach to compute intrinsic part of the $σ_{xy}(ω)$ we find a strong dependence of $σ_{xy}$ on $ω$ in the terahertz range. For example, we find that below 10~THz Co$_3$Al has nearly constant $σ_{xy}$ and that above 10~THz it is reduced by about 50 times. Furthermore, we find a strong dependence of $σ_{xy}$ on the chemical composition. For example, we find that the addition of Al to Fe changes the sign of $σ_{xy}$, while the addition of Co to Fe leads to a nonmonotonic dependence of $σ_{xy}$ on Co concentration.

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Ming Lei, Sinisa Coh. 2024-04-24. Terahertz magneto-optical response in ferromagnetic Fe-Co-Al alloys. https://doi.org/10.1088/1361-648x%2Fad4226

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