Excitonic ferromagnetism in the hexaborides

M. E. Zhitomirsky; T. M. Rice; V. I. Anisimov

doi:10.1038/46207

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Excitonic ferromagnetism in the hexaborides

M. E. Zhitomirsky·T. M. Rice·V. I. Anisimov

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Abstract

A ferromagnet with a small spontaneous moment but with a high Curie temperature can be obtained by doping an excitonic insulator made from a spin triplet exciton condensate. Such a condensate can occur in a semimetal with a small overlap or a semiconductor with a small bandgap. We propose that it is responsible for the unexpected ferromagnetism in the doped hexaboride material Ca_{1-x}La_xB_6.

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M. E. Zhitomirsky, T. M. Rice, V. I. Anisimov. 1999-04-22. Excitonic ferromagnetism in the hexaborides. https://doi.org/10.1038/46207

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