We propose a model for 1/f flux noise in superconducting devices (f is frequency). The noise is generated by the magnetic moments of electrons in defect states which they occupy for a wide distribution of times before escaping. A trapped electron occupies one of the two Kramers-degenerate ground states, between which the transition rate is negligible at low temperature. As a result, the magnetic moment orientation is locked. Simulations of the noise produced by a plausible density of randomly oriented defects yield 1/f noise magnitudes in good agreement with experiments.
Published through SciTech Connect. 01/19/2007. "lbnl--62393" ": KC0202020" Physical Review Letters 98 26 ISSN 0031-9007; PRLTAO FT Clarke, John; Koch, Roger H.; DiVincenzo, David P. COLLABORATION - IBM
