Large N limit of the exactly solvable BCS model: analytics versus numerics

Abstract

We have studied the numerical solutions of Richardson equations of the BCS model in the limit of large number of energy levels at half-filling, and compare them with the analytic results derived by Gaudin and Richardson, which in turn leads to the standard BCS solution. We focus on the location and density of the roots, the eigenvalues of the conserved quantities, and the scaling properties of the total energy for the equally spaced and the two-level models.

Revtex 4 file. 24 pages with 13 figures in text. Minor changes, references added

References in corpus (6)

• Spectroscopy of discrete energy levels in ultrasmall metallic grains
• A Class of Exactly Solvable Pairing Models
• Integrable model for interacting electrons in metallic grains
• Thermodynamic properties of a small superconducting grain
• Electrostatic mapping of nuclear pairing
• New mechanism for the enhancement of $sd$ dominance in interacting boson models

Cited by in corpus (72)

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