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Spin Decoherence in Superconducting Atom Chips

Per Kristian Rekdal·Bo-Sture K. Skagerstam·Ulrich Hohenester·Asier Eiguren
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Abstract

Using a consistent quantum-mechanical treatment for the electromagnetic radiation, we theoretically investigate the magnetic spin-flip scatterings of a neutral two-level atom trapped in the vicinity of a superconducting body. We derive a simple scaling law for the corresponding spin-flip lifetime for such an atom trapped near a superconducting thick slab. For temperatures below the superconducting transition temperature T_c, the lifetime is found to be enhanced by several orders of magnitude in comparison to the case of a normal conducting slab. At zero temperature the spin-flip lifetime is given by the unbounded free-space value.

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Per Kristian Rekdal, Bo-Sture K. Skagerstam, Ulrich Hohenester, Asier Eiguren. 2006-07-07. Spin Decoherence in Superconducting Atom Chips. https://arxiv.org/abs/quant-ph/0603229

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