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Exact correlation functions of the BCS model in the canonical ensemble

Luigi Amico·Andreas Osterloh
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Abstract

We evaluate correlation functions of the BCS model for finite number of particles. The integrability of the Hamiltonian relates it with the Gaudin algebra ${\cal G}[sl(2)]$. Therefore, a theorem that Sklyanin proved for the Gaudin model, can be applied. Several diagonal and off-diagonal correlators are calculated. The finite size scaling behavior of the pairing correlation function is studied.

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Luigi Amico, Andreas Osterloh. 2002-02-11. Exact correlation functions of the BCS model in the canonical ensemble. https://doi.org/10.1103/physrevlett.88.127003

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