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arXiv · 0706.1056

Spontaneous Emission Near Superconducting Bodies

Bo-Sture K. Skagerstam·Per Kristian Rekdal
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Abstract

In the present paper we study the spontaneous photon emission due to a magnetic spin-flip transition of a two-level atom in the vicinity of a dielectric body like a normal conducting metal or a superconductor. For temperatures below the transition temperature T_c of a superconductor, the corresponding spin-flip lifetime is boosted by several orders of magnitude as compared to the case of a normal conducting body. Numerical results of an exact formulation are also compared to a previously derived approximative analytical expression for the spin-flip lifetime and we find an excellent agreement. We present results on how the spin-flip lifetime depends on the temperature T of a superconducting body as well as its thickness H. Finally, we study how non-magnetic impurities as well as possible Eliashberg strong-coupling effects influence the spin-flip rate. It is found that non-magnetic impurities as well as strong-coupling effects have no dramatic impact on the spin-flip lifetime.

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Bo-Sture K. Skagerstam, Per Kristian Rekdal. 2007-06-07. Spontaneous Emission Near Superconducting Bodies. https://doi.org/10.1103/physreva.76.052901

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