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arXiv · 1010.6037

Quantitative evaluation of defect-models in superconducting phase qubits

J. H. Cole·C. Müller·P. Bushev·G. J. Grabovskij·J. Lisenfeld·A. Lukashenko·A. V. Ustinov·A. Shnirman
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Abstract

We use high-precision spectroscopy and detailed theoretical modelling to determine the form of the coupling between a superconducting phase qubit and a two-level defect. Fitting the experimental data with our theoretical model allows us to determine all relevant system parameters. A strong qubit-defect coupling is observed, with a nearly vanishing longitudinal component. Using these estimates, we quantitatively compare several existing theoretical models for the microscopic origin of two-level defects.

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J. H. Cole, C. Müller, P. Bushev, G. J. Grabovskij, J. Lisenfeld, A. Lukashenko, A. V. Ustinov, A. Shnirman. 2010-10-28. Quantitative evaluation of defect-models in superconducting phase qubits. https://doi.org/10.1063/1.3529457

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