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arXiv · 1105.2308

Screening of magnetic fields by charged Bose condensate

Alexander D. Dolgov·Angela Lepidi
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Abstract

The space-space component of the photon polarization operator is calculated in zero frequency limit for a medium with Bose-Einstein condensate (BEC) of electrically charged particles. It is found that the polarization operator tends to a finite value at vanishing photon 3-momentum, as it happens in superconducting media. It means that magnetic fields are exponentially screened in such a medium analogously to the Debye screening of electric charges. At non-zero temperature the screened magnetic field oscillates and contains a contribution which drops only as a power of distance. This phenomenon is unknown for superconductors, even in BEC phase and can be potentially observable.

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Alexander D. Dolgov, Angela Lepidi. 2011-05-11. Screening of magnetic fields by charged Bose condensate. https://doi.org/10.1016/j.physleta.2011.07.017

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