Nonequilibrium and relaxation effects in tunnel superconducting junctions
Journal article, 2017

The specific property of a planar tunnel junction with thin-film diffusive plates and long enough leads is an essential enhancement of its transmission coefficient compared to the bare transparency of the tunnel barrier [1, 2]. In voltage-biased junctions, this creates favorable conditions for strong nonequilibrium of quasiparticles in the junction plates and leads, produced by multiparticle tunneling. We study theoretically the interplay between the nonequilibrium and relaxation processes in such junctions and found that nonequilibrium in the leads noticeably modifies the currentvoltage characteristic at eV > 2D, especially the excess current, whereas strong diffusive relaxation restores the result of the classical tunnel model. At eV > 2D, the diffusive relaxation decreases the peaks of the multiparticle currents. The inelastic relaxation in the junction plates essentially suppresses the n-particle currents (n > 2) by the factor n for odd and n 2 for even n. The results may be important for the problem of decoherence in Josephsonjunction based superconducting qubits.

Josephson junctions

circuit theory

relaxation

nonequilibrium quasiparticles

Author

Eugene Bezuglyi

Chalmers, Microtechnology and Nanoscience (MC2)

Andrey Vasenko

National Research University

E. N. Bratus

Institute for Low Temperature Physics and Engineering

Superconductor Science and Technology

0953-2048 (ISSN) 1361-6668 (eISSN)

Vol. 30 2

Areas of Advance

Nanoscience and Nanotechnology (SO 2010-2017, EI 2018-)

Subject Categories

Physical Sciences

DOI

10.1088/1361-6668/30/2/025011

More information

Latest update

12/29/2020