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Model for l/f Flux Noise in SQUIDs and Qubits

Roger H. Koch·David P. DiVincenzo·John Clarke
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Abstract

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 randomly oriented defects with a density of 5*10^17 m^-2 yield 1/f noise magnitudes in good agreement with experiments.

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Roger H. Koch, David P. DiVincenzo, John Clarke. 2007-05-15. Model for l/f Flux Noise in SQUIDs and Qubits. https://doi.org/10.1103/physrevlett.98.267003

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