Non-quantized penetration of magnetic field in the vortex state of superconductors

@article{Geim2000NonquantizedPO,
  title={Non-quantized penetration of magnetic field in the vortex state of superconductors},
  author={Andre K. Geim and Sergey. V. Dubonos and Irina V. Grigorieva and Kostya S. Novoselov and François M. Peeters and Vitaly A. Schweigert},
  journal={Nature},
  year={2000},
  volume={407},
  pages={55-57}
}
As first pointed out by Bardeen and Ginzburg in the early sixties, the amount of magnetic flux carried by vortices in superconducting materials depends on their distance from the sample edge, and can be smaller than one flux quantum, φ0 = h/2e (where h is Planck's constant and e is the electronic charge). In bulk superconductors, this reduction of flux becomes negligible at sub-micrometre distances from the edge, but in thin films the effect may survive much farther into the material. But the… 

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