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Exact Solution of a Repulsive Fermi Model With Enhanced Superconducting Correlations

H. R. Krishnamurthy·B. Sriram Shastry·IISc·Bangalore
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Abstract

We present the exact solution of a model of interacting fermions in any dimension with a pure repulsive interaction projecting out a given Cooper channel. The solution rests upon the infinite ranged character of the interaction in real space, leading to a functional integral that is dominated by a Gaussian term. The solution produces strong superconducting enhancements and quasi long ranged order in a channel that is not present in the Hamiltonian explicitly, but of the form given by arguments from order by projection.

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H. R. Krishnamurthy, B. Sriram Shastry, IISc, Bangalore. 2000-04-10. Exact Solution of a Repulsive Fermi Model With Enhanced Superconducting Correlations. https://doi.org/10.1103/physrevlett.84.4918

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