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arXiv · 0707.0626

The importance of thermal disorder and electronic occupation for the T-dependence of the optical conductivity in FeSi and MnSi

T. Jarlborg
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Abstract

The spectral weight (SW) for optical transitions in FeSi and MnSi are calculated as function of temperature by means of LMTO-LDA band calculations. The main effects, caused by structural disorder and electronic Fermi-Dirac distribution, act oppositely on the T-dependence of the SW, while the variation of the magnetic moment in MnSi has only a minor effect. The calculations agree with the experimental findings of an increasing SW in FeSi and a decreasing SW in MnSi as function of T. The results can be understood from the change of the bandstructure with disorder.

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T. Jarlborg. 2007-07-04. The importance of thermal disorder and electronic occupation for the T-dependence of the optical conductivity in FeSi and MnSi. https://doi.org/10.1103/physrevb.76.205105

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