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arXiv · 0905.3731

Signatures of electron-boson coupling in half-metallic ferromagnet Mn$_5$Ge$_3$: study of electron self-energy $\Sigma(\omega)$ obtained from infrared spectroscopy

S. V. Dordevic·N. Stojilovic·L. W. Kohlman·Rongwei Hu·C. Petrovic
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Abstract

We report results of our infrared and optical spectroscopy study of a half-metallic ferromagnet Mn$_5$Ge$_3$. This compound is currently being investigated as a potential injector of spin polarized currents into germanium. Infrared measurements have been performed over a broad frequency (50 - 50000 cm$^{-1}$) and temperature (10 - 300 K) range. From the complex optical conductivity $\sigma(\omega)$ we extract the electron self-energy $\Sigma(\omega)$. The calculation of $\Sigma(\omega)$ is based on novel numerical algorithms for solution of systems of non-linear equations. The obtained self-energy provides a new insight into electron correlations in Mn$_5$Ge$_3$. In particular, it reveals that charge carriers may be coupled to bosonic modes, possibly of magnetic origin.

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S. V. Dordevic, N. Stojilovic, L. W. Kohlman, Rongwei Hu, C. Petrovic. 2009-05-22. Signatures of electron-boson coupling in half-metallic ferromagnet Mn$_5$Ge$_3$: study of electron self-energy $\Sigma(\omega)$ obtained from infrared spectroscopy. https://doi.org/10.1103/physrevb.80.115114

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