Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Signatures of electron-boson coupling in half-metallic ferromagnet
  Mn$_5$Ge$_3$: study of electron self-energy $\Sigma(\omega)$ obtained from
  infrared spectroscopy   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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The categories of this paper are: mtrl-th
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The categories of this paper are: supr-con
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
11
The categories of this paper are: hep-lat
3
The categories of this paper are: physics
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The categories of this paper are: atom-ph
31
The categories of this paper are: ao-sci
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
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The categories of this paper are: patt-sol
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The categories of this paper are: q-fin
13
The categories of this paper are: quant-ph
8
The categories of this paper are: hep-ex
34
The categories of this paper are: chem-ph
12
The categories of this paper are: nucl-th