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arXiv · 0810.4415

Symmetric and non-symmetric vortex-antivortex molecules in fourfold superconducting geometry

R. Geurts·M. V. Milošević·F. M. Peeters
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Abstract

In submicron superconducting squares in a homogeneous magnetic field, Ginzburg-Landau theory may admit solutions of the vortex-antivortex type, conforming with the symmetry of the sample [Chibotaru et al., Nature 408, 833 (2000)]. Here we show that these fascinating, but never experimentally observed states, can be enforced by artificial fourfold pinning, with their diagnostic features enhanced by orders of magnitude. The second-order nucleation of vortex-antivortex molecules can be driven either by temperature or applied magnetic field, with stable asymmetric vortex-antivortex equilibria found on its path.

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R. Geurts, M. V. Milošević, F. M. Peeters. 2008-10-24. Symmetric and non-symmetric vortex-antivortex molecules in fourfold superconducting geometry. https://doi.org/10.1103/physrevlett.97.137002

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