2005/01/07 by Michael Mueck, Matthias Korn, C. G. A. Mugford +2
Physics and Astronomy · #cond-mat.supr-con #cond-mat.mes-hall
paper · pdf · doi:10.1063/1.1846157
published as Appl. Phys. Lett. 86, 012510 (2005) · 3 pages, 2 figures
arxiv created 2005/01/07 · arxiv updated 2009/12/01
Critical current fluctuations with a 1/ f spectral density (f is frequency) are potentially a limiting source of intrinsic decoherence in superconducting quantum bits (qubits) based on Josephson tunnel junctions. Prior measurements of this noise were made at nonzero voltages whereas qubits are operated in the zero voltage state. We report measurements of 1/ f noise in a dc superconducting quantum interference device first, coupled to a resonant tank circuit and operated in a dispersive mode at zero voltage, and, second, operated conventionally with a current bias in the voltage regime. Both measurements yield essentially the same magnitude of critical current 1/ f noise.