Bloch band dynamics of a Josephson junction in an inductive environment

Anno: 2015

Autori: WeiYAl T., Rastelli G., Matei I., Pop I.M., Buisson O., Hekking F.W.J., Guichard W.

Affiliazione autori: CNRS, Inst Neel, F-38042 Grenoble 9, France; Univ Grenoble 1, F-38042 Grenoble 9, France; Univ Konstanz, Fachbereich Phys, D-78457 Constance, Germany; Univ Grenoble 1, CNRS, LPMMC UMR 5493, F-38042 Grenoble, France; Yale Univ, Dept Appl Phys, New Haven, CT 06520 USA

Abstract: We have measured the current-voltage characteristics of a Josephson junction with tunable Josephson energy EJ embedded in an inductive environment provided by a chain of SQUIDs. Such an environment induces localization of the charge on the junction, which results in an enhancement of the zero-bias resistance of the circuit. We explain this result quantitatively in terms of the Bloch band dynamics of the localized charge. This dynamics is governed by charge diffusion in the lowest Bloch band of the Josephson junction as well as by Landau-Zener transitions out of the lowest band into the higher bands. In addition, the frequencies corresponding to the self-resonant modes of the SQUID array exceed the Josephson energy EJ of the tunable junction, which results in a renormalization of EJ, and, as a consequence, an increase of the effective bandwidth of the lowest Bloch band.


Volume: 91 (1)      Da Pagina: 014507  A:

Maggiori informazioni: T.W. acknowledges support from the Grenoble Nanoscience Foundation. G.R acknowledges support from the EU FP7 Marie Curie Zukunftskolleg Incoming Fellowship Programme, University of Konstanz (Grant No. 291784). F.H. and W.G. are supported by Institut universitaire de France. W.G. also acknowledges support from the European Research council (Grant No. 306731). The authors thank N. Roch for fruitful discussions and M. Vanevic for useful comments on the manuscript.
Parole chiavi: josephson junctions
DOI: 10.1103/PhysRevB.91.014507