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arXiv · 0705.3327

Revelation of the role of impurities and conduction electron density in the high resolution photoemission study of ferromagnetic hexaborides

Kalobaran Maiti·V. R. R. Medicherla·Swapnil Patil·Ravi Shankar Singh
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Abstract

We investigate the temperature evolution of the electronic structure of ferromagnetic CaB$_6$ using ultra-high resolution photoemission spectroscopy; electronic structure of paramagnetic LaB$_6$ is used as a reference. High resolution spectra of CaB$_6$ reveal finite density of states at the Fermi level, $ε_F$ at all the temperatures and evidence of impurity induced localized features in the vicinity of $ε_F$, which are absent in the spectra of LaB$_6$. Analysis of the high resolution spectra suggests that disorder in B-sublattice inducing partial localization in the mobile electrons and low electron density at $ε_F$ is important to achieve ferromagnetism in these systems.

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Kalobaran Maiti, V. R. R. Medicherla, Swapnil Patil, Ravi Shankar Singh. 2007-05-23. Revelation of the role of impurities and conduction electron density in the high resolution photoemission study of ferromagnetic hexaborides. https://doi.org/10.1103/physrevlett.99.266401

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