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Phase separation in the particle-hole asymmetric Hubbard model

M. Eckstein·M. Kollar·M. Potthoff·D. Vollhardt
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Abstract

The paramagnetic phase diagram of the Hubbard model with nearest-neighbor (NN) and next-nearest-neighbor (NNN) hopping on the Bethe lattice is computed at half-filling and in the weakly doped regime using the self-energy functional approach for dynamical mean-field theory. NNN hopping breaks the particle-hole symmetry and leads to a strong asymmetry of the electron-doped and hole-doped regimes. Phase separation occurs at and near half-filling, and the critical temperature of the Mott transition is strongly suppressed.

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M. Eckstein, M. Kollar, M. Potthoff, D. Vollhardt. 2006-10-30. Phase separation in the particle-hole asymmetric Hubbard model. https://doi.org/10.1103/physrevb.75.125103

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