Abrikosov vortex escape from a columnar defect as a topological electronic transition in vortex core

A. S. Mel'nikov; A. V. Samokhvalov

doi:10.1134/s0021364011220085

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arXiv · 1106.1971

Abrikosov vortex escape from a columnar defect as a topological electronic transition in vortex core

A. S. Mel'nikov·A. V. Samokhvalov

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Abstract

We study microscopic scenario of vortex escape from a columnar defect under the influence of a transport current. For defect radii smaller than the superconducting coherence length the depinning process is shown to be a consequence of two subsequent topological electronic transitions in a trapped vortex core. The first transition at a critical current $j_L$ is associated with the opening of Fermi surface segments corresponding to the creation of a vortex--antivortex pair bound to the defect. The second transition at a certain current $j_d > j_L$ is caused by merging of different Fermi surface segments, which accompanies the formation of a freely moving vortex.

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A. S. Mel'nikov, A. V. Samokhvalov. 2011-06-10. Abrikosov vortex escape from a columnar defect as a topological electronic transition in vortex core. https://doi.org/10.1134/s0021364011220085

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