Electron-hole symmetry and solutions of Richardson pairing model

W. V. Pogosov; N. S. Lin; V. R. Misko

doi:10.1140/epjb/e2013-40234-9

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arXiv · 1304.0849

Electron-hole symmetry and solutions of Richardson pairing model

W. V. Pogosov·N. S. Lin·V. R. Misko

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Abstract

Richardson approach provides an exact solution of the pairing Hamiltonian. This Hamiltonian is characterized by the electron-hole pairing symmetry, which is however hidden in Richardson equations. By analyzing this symmetry and using an additional conjecture, fulfilled in solvable limits, we suggest a simple expression of the ground state energy for an equally-spaced energy-level model, which is applicable along the whole crossover from the superconducting state to the pairing fluctuation regime. Solving Richardson equations numerically, we demonstrate a good accuracy of our expression.

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W. V. Pogosov, N. S. Lin, V. R. Misko. 2013-04-03. Electron-hole symmetry and solutions of Richardson pairing model. https://doi.org/10.1140/epjb%2Fe2013-40234-9

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