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Theory of Ferromagnetism in Ca1-xLaxB6

Shuichi Murakami·Ryuichi Shindou·Naoto Nagaosa·Andrei S. Mishchenko
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Abstract

Novel ferromagnetism in Ca$_{1-x}$La$_{x}$B$_6$ is studied in terms of the Ginzburg-Landau theory for excitonic order parameters, taking into account symmetry of the wavefunctions. We found that the minima of the free energy break both inversion and time-reversal symmetries, while the product of these two remains preserved. This explains various novelties of the ferromagnetism and predicts a number of magnetic properties, including the magnetoelectric effect, which can be tested experimentally.

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Shuichi Murakami, Ryuichi Shindou, Naoto Nagaosa, Andrei S. Mishchenko. 2002-02-15. Theory of Ferromagnetism in Ca1-xLaxB6. https://doi.org/10.1103/physrevlett.88.126404

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