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Comment on `Spin Decoherence in Superconducting Atom Chips'

Stefan Scheel·E. A. Hinds·P. L. Knight
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Abstract

We comment on a recent paper [Phys. Rev. Lett. 97, 070401 (2006): quant-ph/0603229] concerning rubidium atoms trapped near a superconducting niobium surface at ~4K. This seeks to calculate the rate of atomic spin flips induced by thermal magnetic noise. We point out that the calculation is in error by a large factor because it is based on the two-fluid model of superconductivity. This model gives a poor description of electromagnetic dissipation just below the critical temperature because it cannot incorporate the case II coherences of a fuller quantum theory.

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Stefan Scheel, E. A. Hinds, P. L. Knight. 2006-10-12. Comment on `Spin Decoherence in Superconducting Atom Chips'. https://arxiv.org/abs/quant-ph/0610095

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