Korshunov instantons in a superconductor at elevated bias current

Daniel Otten and Fabian Hassler
Phys. Rev. B 96, 125433 – Published 22 September 2017

Abstract

Even at zero temperature dissipation reduces quantum fluctuations and tends to localize particles. A notable exception is the nonlinear dissipation due to quasiparticle tunneling in a Josephson junction. It is well known that quasiparticle dissipation does not suppress tunneling of the superconducting phase difference between next-nearest metastable phase states even though tunneling to the nearest phase state is suppressed. The reason is that the dissipative action admits an instanton solution, the so-called Korshunov instanton. Here, we analyze this model at elevated bias current I. We find that besides the known regime where the logarithm of the tunneling rate scales as I2/3 there is a novel regime with a scaling I2. We argue that the increased tunneling rate that derives from the elevated bias current is favorable for experimental verification of the Korshunov instantons.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Received 8 May 2017
  • Revised 12 September 2017

DOI:https://doi.org/10.1103/PhysRevB.96.125433

©2017 American Physical Society

Physics Subject Headings (PhySH)

Condensed Matter, Materials & Applied Physics

Authors & Affiliations

Daniel Otten and Fabian Hassler

  • JARA-Institute for Quantum Information, RWTH Aachen University, D-52056 Aachen, Germany

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 96, Iss. 12 — 15 September 2017

Reuse & Permissions
Access Options

Authorization Required


×
×

Images

×

Sign up to receive regular email alerts from Physical Review B

Log In

Cancel
×

Search


Article Lookup

Paste a citation or DOI

Enter a citation
×