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Deconfinement of Vortices with Continuously Variable Fractions of the Unit Flux Quanta in Two-Gap Superconductors

Jun Goryo·Singo Soma·Hiroshi Matsukawa
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Abstract

We propose a new stage of confiment-decofinment transition, which can be observed in laboratory. In two-gap superconductors (SCs), two kinds of vortex exist and each of them carries a continuously variable fraction of the unit flux quanta Phi_0=h c / 2 e. The confined state of these two is a usual vortex and stable in the low temperature region of the system under a certain magnetic field above H_c1. We see an analogy to quarks in a charged pion. An entropy gain causes two fractional vortices to be deconfined above a certain temperature.

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Jun Goryo, Singo Soma, Hiroshi Matsukawa. 2007-08-09. Deconfinement of Vortices with Continuously Variable Fractions of the Unit Flux Quanta in Two-Gap Superconductors. https://doi.org/10.1209/0295-5075%2F80%2F17002

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