We report on the noise properties of ion-irradiated YBa2Cu3O7 Josephson junctions. This work aims at investigating the linewidth of the Josephson oscillation with a detector response experiment at ≃132 GHz. Experimental results are compared with a simple analytical model based on the Likharev-Semenov equation and the de Gennes dirty limit approximation. We show that the main source of low-frequency fluctuations in these junctions is the broadband Johnson noise and that the excess (f1) noise contribution does not prevail in the temperature range of interest, as reported in some other types of high-Tc superconducting Josephson junctions. Finally, we discuss the interest of ion-irradiated junctions to implement frequency-tunable oscillators consisting of synchronized arrays of Josephson junctions.
@article{arxiv.1603.08466,
title = {Josephson oscillation linewidth of ion-irradiated YBa$_2$Cu$_3$O$_7$ junctions},
author = {A. Sharafiev and M. Malnou and C. Feuillet-Palma and C. Ulysse and P. Febvre and J. Lesueur and N. Bergeal},
journal= {arXiv preprint arXiv:1603.08466},
year = {2016}
}