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arXiv · 1912.05692

Ground-state energy of a Richardson-Gaudin integrable BCS model

Yibing Shen·Phillip S. Isaac·Jon Links
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Abstract

We investigate the ground-state energy of a Richardson-Gaudin integrable BCS model, generalizing the closed and open p+ip models. The Hamiltonian supports a family of mutually commuting conserved operators satisfying quadratic relations. From the eigenvalues of the conserved operators we derive, in the continuum limit, an integral equation for which a solution corresponding to the ground state is established. The energy expression from this solution agrees with the BCS mean-field result.

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Yibing Shen, Phillip S. Isaac, Jon Links. 2019-12-11. Ground-state energy of a Richardson-Gaudin integrable BCS model. https://doi.org/10.21468/scipostphyscore.2.1.001

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