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Parity effect in a small superconducting grain: A rigorous result

Guang-Shan Tian·Lei-Han Tang
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Abstract

The parity effect in an ultra-small superconducting grain is examined. By applying a generalized version of Lieb's spin-reflection positivity technique, we show rigorously that the parity parameter $Δ_P$ is nonvanishing in such a system. A positive lower bound for $Δ_P$ is derived.

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Guang-Shan Tian, Lei-Han Tang. 1998-08-19. Parity effect in a small superconducting grain: A rigorous result. https://doi.org/10.1103/physrevb.58.12333

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