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Optical evidence for heavy charge carriers in FeGe

V. Guritanu·D. van der Marel·J. Teyssier·T. Jarlborg·H. Wilhelm·M. Schmidt·F. Steglich
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Abstract

The optical spectrum of the cubic helimagnetic metal FeGe has been investigated in the frequency range from 0.01 - 3.1 eV for different temperatures from 30 K to 296 K. The optical conductivity shows the evolution of a low energy (0.22 eV) interband transition and the development of a narrow free carrier response with a strong energy and temperature dependence. The frequency dependent effective mass and scattering rate derived from the optical data indicate the formation of dressed quasi-particles with a mass renormalization factor of 12. Similar to FeSi the spectral weight in FeGe is not recovered over a broad frequency range, an effect usually attributed to the influence of the on-site Coulomb interaction.

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V. Guritanu, D. van der Marel, J. Teyssier, T. Jarlborg, H. Wilhelm, M. Schmidt, F. Steglich. 2007-02-14. Optical evidence for heavy charge carriers in FeGe. https://doi.org/10.1103/physrevb.75.155114

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