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Phase Separation close to the density-driven Mott transition in the Hubbard-Holstein model

M. Capone·G. Sangiovanni·C. Castellani·C. Di Castro·M. Grilli
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Abstract

The density driven Mott transition is studied by means of Dynamical Mean-Field Theory in the Hubbard-Holstein model, where the Hubbard term leading to the Mott transition is supplemented by an electron-phonon (e-ph) term. We show that an intermediate e-ph coupling leads to a first-order transition at T=0, which is accompanied by phase separation between a metal and an insulator. The compressibility in the metallic phase is substantially enhanced. At quite larger values of the coupling a polaronic phase emerges coexisting with a non-polaronic metal.

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M. Capone, G. Sangiovanni, C. Castellani, C. Di Castro, M. Grilli. 2004-01-28. Phase Separation close to the density-driven Mott transition in the Hubbard-Holstein model. https://doi.org/10.1103/physrevlett.92.106401

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