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arXiv · 1208.2193

Electronic structure, optical and magnetic properties of Co$_{2}$FeGe Heusler alloy films

N. V. Uvarov·Y. V. Kudryavtsev·A. F. Kravets·A. Ya. Vovk·R. P. Borges·M. Godinho·V. Korenivski
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Abstract

Optical properties of ferromagnetic half-metallic full-Heusler Co$_{2}$FeGe alloy are investigated experimentally and theoretically. Co$_{2}$FeGe thin films were obtained by DC magnetron sputtering and show the saturation magnetization at $T$=10 K of $m\approx$5.6 $\mu_{B}$/f.u., close to the value predicted by the Slater-Pauling rule. First-principles calculations of the electronic structure and the dielectric tensor are performed using the full-potential linearized-augmented-plane-wave method in the generalized gradient (GGA) and GGA+U approximations. The measured interband optical conductivity spectrum for the alloy exhibits a strong absorption band in the 1 - 4 eV energy range with pronounced fine structure, which agrees well with the calculated half-metallic spectrum of the system, suggesting a near perfect spin-polarization in the material.

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N. V. Uvarov, Y. V. Kudryavtsev, A. F. Kravets, A. Ya. Vovk, R. P. Borges, M. Godinho, V. Korenivski. 2012-08-10. Electronic structure, optical and magnetic properties of Co$_{2}$FeGe Heusler alloy films. https://doi.org/10.1063/1.4752870

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