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arXiv · 1008.3590

Stimulation of the fluctuation superconductivity by the PT-symmetry

N. M. Chtchelkatchev·A. A. Golubov·T. I. Baturina·V. M. Vinokur
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Abstract

We discuss fluctuations near the second order phase transition where the free energy has an additional non-Hermitian term. The spectrum of the fluctuations changes when the odd-parity potential amplitude exceeds the critical value corresponding to the PT-symmetry breakdown in the topological structure of the Hilbert space of the effective non-Hermitian Hamiltonian. We calculate the fluctuation contribution to the differential resistance of a superconducting weak link and find the manifestation of the PT-symmetry breaking in its temperature evolution. We successfully validate our theory by carrying out measurements of far from equilibrium transport in mesoscale-patterned superconducting wires.

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N. M. Chtchelkatchev, A. A. Golubov, T. I. Baturina, V. M. Vinokur. 2012-09-05. Stimulation of the fluctuation superconductivity by the PT-symmetry. https://doi.org/10.1103/physrevlett.109.150405

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