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Observation of a New Mechanism of Spontaneous Generation of Magnetic Flux in a Superconductor

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 Added by Ariel Maniv
 Publication date 2004
  fields Physics
and research's language is English
 Authors A. Maniv




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We report the discovery of a new mechanism of spontaneous generation of a magnetic flux in a superconductor cooled through $T_c$. The sign of the spontaneous flux changes randomly from one cooldown to the next, and follows a Gaussian distribution. The width of the distribution increases with the size of the temperature gradient in the sample. Our observations appear inconsistent with the well known mechanisms of flux generation. The dependence on the temperature gradient suggests that the flux may be generated through an instability of the thermoelectric superconducting-normal quasiparticle counterflow.



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