Phase diagram of exciton condensate in doped two-band Hubbard model

Jan Kunes

doi:10.1103/physrevb.90.235140

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arXiv · 1410.5198

Phase diagram of exciton condensate in doped two-band Hubbard model

Jan Kunes

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Abstract

Using the dynamical mean-field approximation we investigate formation of excitonic condensate in the two-band Hubbard model in the vicinity of the spin-state transition. With temperature and band filling as the control parameters we realize all symmetry allowed spin-triplet excitonic phases, some exhibiting a ferromagnetic polarization. While the transitions are first-order at low temperatures, at elevated temperatures continuous transitions are found that give rise to a multi-critical point. Rapid but continuous transition between ferromagnetic and non-magnetic excitonic phases allows switching of uniform magnetization by small changes of chemical potential.

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Jan Kunes. 2014-10-20. Phase diagram of exciton condensate in doped two-band Hubbard model. https://doi.org/10.1103/physrevb.90.235140

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