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arXiv · cond-mat/9705290

Vortex Pinning and Non-Hermitian Quantum Mechanics

Naomichi Hatano·David R. Nelson
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Abstract

A delocalization phenomenon is studied in a class of non-Hermitian random quantum-mechanical problems. Delocalization arises in response to a sufficiently large constant imaginary vector potential. The transition is related to depinning of flux lines from extended defects in type-II superconductors subject to a tilted external magnetic field. The physical meaning of the complex eigenvalues and currents of the non-Hermitian system is elucidated in terms of properties of tilted vortex lines. The singular behavior of the penetration length describing stretched exponential screening of a perpendicular magnetic field (transverse Meissner effect), the surface transverse magnetization, and the trapping length are determined near the flux-line depinning point.

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Naomichi Hatano, David R. Nelson. 1997-07-02. Vortex Pinning and Non-Hermitian Quantum Mechanics. https://doi.org/10.1103/physrevb.56.8651

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