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Superconductivity in Ultrasmall Grains: Introduction to Richardson's Exact Solution

Jan von Delft·Fabian Braun
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Abstract

Studies of pairing correlations in ultrasmall metallic grains have commonly been based on a simple reduced BCS-model describing the scattering of pairs of electrons between discrete energy levels that come in time-reversed pairs. This model has an exact solution, worked out by Richardson in the context of nuclear physics in the 1960s. Here we give a tutorial introduction to his solution, and use it to check the quality of various previous treatments of this model.

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Jan von Delft, Fabian Braun. 1999-11-04. Superconductivity in Ultrasmall Grains: Introduction to Richardson's Exact Solution. https://arxiv.org/abs/cond-mat/9911058

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