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arXiv · 1710.04467

Competing phases in a model of Pr-based cobaltites

Andrii Sotnikov·Jan Kuneš
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Abstract

Motivated by the physics of Pr-based cobaltites, we study the effect of the external magnetic field in the hole-doped two-band Hubbard model close to instabilities toward the excitonic condensation and ferromagnetic ordering. Using the dynamical mean-field theory we observe a field-driven suppression of the excitonic condensate. The onset of a magnetically ordered phase at the fixed chemical potential is accompanied by a sizable change of the electron density. This leads us to predict that Pr$^{3+}$ abundance increases on the high-field side of the transition.

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Andrii Sotnikov, Jan Kuneš. 2017-12-04. Competing phases in a model of Pr-based cobaltites. https://doi.org/10.1103/physrevb.96.245102

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