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arXiv · cond-mat/0510279

Spatial Structure of the Cooper Pair

Alan M. Kadin
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Abstract

The Cooper pair is generally analyzed in momentum space, but its real-space structure also follows directly from the BCS theory. It is shown here that this leads to a spherically symmetrical quasi-atomic wavefunction, with an identical "onion-like" layered structure for each of the electrons constituting the Cooper pair, with charge layers ~ 0.1 nm and a radius ~ 100 nm for a classic BCS superconductor. This charge modulation induces a corresponding charge modulation in the background ionic lattice, and the attractive interaction between these two opposite charge modulations produces the binding energy of the Cooper pair. This physically-based interaction potential is similar to that in the simple BCS approximation. The implications of this real-space picture for understanding conventional and exotic superconductors are discussed.

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Alan M. Kadin. 2005-10-11. Spatial Structure of the Cooper Pair. https://doi.org/10.1007/s10948-006-0198-z

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