Direct Transition Between a Singlet Mott Insulator and a Superconductor

M. Capone; M. Fabrizio; E. Tosatti

doi:10.1103/physrevlett.86.5361

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Direct Transition Between a Singlet Mott Insulator and a Superconductor

M. Capone·M. Fabrizio·E. Tosatti

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Abstract

We argue that a normal Fermi liquid and a singlet, spin gapped Mott insulator cannot be continuously connected, and that some intermediate phase must intrude between them. By explicitly working out a case study where the singlet insulator is stabilized by orbital degeneracy and an inverted Hund's rule coupling, mimicking a Jahn-Teller effect, we find that the intermediate phase is a superconductor.

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M. Capone, M. Fabrizio, E. Tosatti. 2001-05-15. Direct Transition Between a Singlet Mott Insulator and a Superconductor. https://doi.org/10.1103/physrevlett.86.5361

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