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arXiv · 1002.2289

Multi-condensate states in BCS superconductors

Eldad Bettelheim
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Abstract

A BCS (Bardeen-Cooper-Schrieffer) superconductor, which is placed out of equilibrium, can develop quantum instabilities, which manifest themselves in oscillations of the superconductor's order parameter (pairing amplitude $Δ$). These instabilities are a manifestations of the Cooper instability. Inelastic collisions are essential in resolving those instabilities. Incorporating the quantum instabilities and collisions in a unified approach based on Richardson's exact solution of the pairing Hamiltonian, we find that a BCS superconductor may end up in a state in which the spectrum has more than one gap.

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Eldad Bettelheim. 2010-07-08. Multi-condensate states in BCS superconductors. https://doi.org/10.1209/0295-5075%2F90%2F67002

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