Current noise of a superconducting single-electron transistor coupled to a resonator

T. J. Harvey, D. A. Rodrigues, and A. D. Armour
Phys. Rev. B 78, 024513 – Published 16 July 2008

Abstract

We analyze the current and zero-frequency current noise properties of a superconducting single-electron transistor (SSET) coupled to a resonator, focusing on the regime where the SSET is operated in the vicinity of the Josephson quasiparticle resonance. We consider a range of coupling strengths and resonator frequencies to reflect the fact that in practice the system can be tuned to quite a high degree with the resonator formed either by a nanomechanical oscillator or a superconducting stripline fabricated in close proximity to the SSET. For very weak couplings the SSET acts on the resonator like an effective thermal bath. In this regime the current characteristics of the SSET are only weakly modified by the resonator. Using a mean-field approach, we show that the current noise is nevertheless very sensitive to the correlations between the resonator and the SSET charge. For stronger couplings, the SSET can drive the resonator into limit-cycle states where self-sustained oscillation occurs and we find that regions of well-defined bistability exist. Dynamical transitions into and out of the limit-cycle state are marked by strong fluctuations in the resonator energy, but these fluctuations are suppressed within the limit-cycle state. We find that the current noise of the SSET is strongly influenced by the fluctuations in the resonator energy and hence should provide a useful indicator of the resonator’s dynamics.

  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
  • Figure
9 More
  • Received 30 April 2008

DOI:https://doi.org/10.1103/PhysRevB.78.024513

©2008 American Physical Society

Authors & Affiliations

T. J. Harvey, D. A. Rodrigues, and A. D. Armour

  • School of Physics and Astronomy, University of Nottingham, Nottingham NG7 2RD, United Kingdom

Article Text (Subscription Required)

Click to Expand

References (Subscription Required)

Click to Expand
Issue

Vol. 78, Iss. 2 — 1 July 2008

Reuse & Permissions
Access Options
Author publication services for translation and copyediting assistance advertisement

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
×