Stimulation of the Fluctuation Superconductivity by $\mathsc{P}\mathcal{T}$ Symmetry

Stimulation of the Fluctuation Superconductivity by $P T$ Symmetry

N. M. Chtchelkatchev, A. A. Golubov, T. I. Baturina, and V. M. Vinokur

Phys. Rev. Lett. 109, 150405 – Published 9 October 2012

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 $P T$ -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 $P T$ -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.

Received 6 May 2012

DOI:https://doi.org/10.1103/PhysRevLett.109.150405

Authors & Affiliations

N. M. Chtchelkatchev^1,2, A. A. Golubov³, T. I. Baturina^4,5, and V. M. Vinokur⁴

¹Institute for High Pressure Physics, Russian Academy of Sciences, Troitsk 142190, Moscow region, Russia
²Department of Theoretical Physics, Moscow Institute of Physics and Technology, 141700 Moscow, Russia
³Faculty of Science and Technology and MESA+ Institute of Nanotechnology, University of Twente, Enschede, The Netherlands
⁴Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439, USA
⁵A. V. Rzhanov Institute of Semiconductor Physics SB RAS, Novosibirsk, 630090 Russia