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Multiquantum Vortices in Conventional Superconductors with Columnar Defects Near the Upper Critical Field

Gregory M. Braverman·Sergey A. Gredeskul·Yshai Avishai
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Abstract

Equilibrium vortex configuration in conventional type II superconductors containing columnar defects is theoretically investigated. Near the upper critical field a single defect causes a strong local deformation of the vortex lattice. This deformation has $C_3$ or $C_6$ point symmetry, whose character strongly depends on the vortex-defect interaction. If the interaction is attractive, the vortices can collapse onto defect, while in the case of repulsion the regions free of vortices appear near a defect. Increasing the applied magnetic field results in an abrupt change of the configuration of vortices giving rise to reentering transitions between configurations with $C_3$ or $C_6$ symmetry. In the case of a small concentration of defects these transitions manifest themselves as jumps of magnetization and discontinuties of the magnetic susceptibility.

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Gregory M. Braverman, Sergey A. Gredeskul, Yshai Avishai. 1998-02-26. Multiquantum Vortices in Conventional Superconductors with Columnar Defects Near the Upper Critical Field. https://doi.org/10.1103/physrevb.57.13899

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