Abrikosov vortices

In superconductivity, an Abrikosov vortex is a vortex of supercurrent in a type-II superconductor theoretically predicted by Alexei Abrikosov in 1957. The supercurrent circulates around the normal (i.e. non-superconducting) core of the vortex. The core has a size ${\displaystyle \sim \xi }$ — the superconducting coherence length (parameter of a Ginzburg-Landau theory). The supercurrents decay on the distance about ${\displaystyle \lambda }$ (London penetration depth) from the core. Note that in type-II superconductors ${\displaystyle \lambda >\xi /{\sqrt {2}}}$. The circulating supercurrents induce magnetic fields with the total flux equal to a single flux quantum ${\displaystyle \Phi _{0}}$. Therefore, an Abrikosov vortex is often called a fluxon.

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