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Ferromagnetism and superstructure in Ca_{1-x}La_xB_6

Victor Barzykin·Lev P. Gor'kov
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Abstract

We critically investigate the model of a doped excitonic insulator, which recently has been invoked to explain some experimental properties of the ferromagnetic state in Ca_{1-x}La_xB_6. We demonstrate that the ground state of this model is intrinsically unstable towards the appearance of a superstructure. In addition, the model would lead to a phase separation regime and the domain structure which may be prevented by the Coulomb forces only. Recent experiments indicate that a superstructure may indeed show up in this material.

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Victor Barzykin, Lev P. Gor'kov. 1999-06-26. Ferromagnetism and superstructure in Ca_{1-x}La_xB_6. https://doi.org/10.1103/physrevlett.84.2207

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