Fluctuations From Edge Defects in Superconducting Resonators

C. Neill; A. Megrant; R. Barends; Yu Chen; B. Chiaro; J. Kelly; J. Y. Mutus; P. J. J. O'Malley; D. Sank; J. Wenner; T. C. White; Yi Yin; A. N. Cleland; John M. Martinis

doi:10.1063/1.4818710

arXiv · 1306.3718

Fluctuations From Edge Defects in Superconducting Resonators

C. Neill·A. Megrant·R. Barends·Yu Chen·B. Chiaro·J. Kelly·J. Y. Mutus·P. J. J. O'Malley·D. Sank·J. Wenner·T. C. White·Yi Yin·A. N. Cleland·John M. Martinis

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Abstract

Superconducting resonators, used in astronomy and quantum computation, couple strongly to microscopic two-level defects. We monitor the microwave response of superconducting resonators and observe fluctuations in dissipation and resonance frequency. We present a unified model where the observed dissipative and dispersive effects can be explained as originating from a bath of fluctuating two-level systems. From these measurements, we quantify the number and distribution of the defects.

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C. Neill, A. Megrant, R. Barends, Yu Chen, B. Chiaro, J. Kelly, J. Y. Mutus, P. J. J. O'Malley, D. Sank, J. Wenner, T. C. White, Yi Yin, A. N. Cleland, John M. Martinis. 2013-06-17. Fluctuations From Edge Defects in Superconducting Resonators. https://doi.org/10.1063/1.4818710

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