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Magneto-optical Kerr effect in $Eu_{1-x}Ca_{x}B_{6}$

G. Caimi·S. Broderick·H. R. Ott·L. Degiorgi·A. D. Bianchi·Z. Fisk
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Abstract

We have measured the magneto-optical Kerr rotation of ferromagnetic $Eu_{1-x}Ca_{x}B_{6}$ with x=0.2 and 0.4, as well as of $YbB_{6}$ serving as the non-magnetic reference material. As previously for $EuB_{6}$, we could identify a feature at 1 $eV$ in the Kerr response which is related with electronic transitions involving the localized 4f electron states. The absence of this feature in the data for $YbB_{6}$ confirms the relevance of the partially occupied 4f states in shaping the magneto-optical features of $Eu$-based hexaborides. Disorder by $Ca$-doping broadens the itinerant charge carrier contribution to the magneto-optical spectra.

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G. Caimi, S. Broderick, H. R. Ott, L. Degiorgi, A. D. Bianchi, Z. Fisk. 2003-08-14. Magneto-optical Kerr effect in $Eu_{1-x}Ca_{x}B_{6}$. https://doi.org/10.1103/physrevb.69.012406

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