Abstract
The frequency dependences of the real part ε1(ω) and imaginary part ε2(ω) of the complex dielectric constant of the Co2NiAl Heusler alloy are studied in a region of spectrum of 0.08–5 eV. It was found that the character of variations of the spectral parameters of the Co2NiAl ally is typical of media with metallic conductivity. In the IR region, the mechanism of intraband acceleration of electrons by the field of light wave dominates. The contribution of interband electron transitions is marked even at the energies E ≥ 0.15 eV. Results of the investigations are discussed based on the performed electronic structure calculations. It is shown that the main contribution to the resulting optical conductivity dependence is made by interband electron transitions in the band with spins opposite to the magnetization direction.
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ACKNOWLEDGMENTS
This work was performed within the framework of the state task of the Ministry of Science and Higher Education of the Russian Federation (theme Electron, no. АААА-А18-118020190098-5) and was supported in part by the Russian Foundation for Basic Research (project no. 16-52-48012).
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Shreder, E.I., Lukoyanov, A.V., Makhnev, A.A. et al. Electronic Structure and Optical Properties of the Co2NiAl Heusler Alloy. Phys. Metals Metallogr. 120, 729–732 (2019). https://doi.org/10.1134/S0031918X19080155
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DOI: https://doi.org/10.1134/S0031918X19080155