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arXiv · 1512.02553

Analysis of high quality superconducting resonators: consequences for TLS properties in amorphous oxides

Jonathan Burnett·Lara Faoro·Tobias Lindstrom
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Abstract

$1/f$ noise caused by microscopic Two-Level Systems (TLS) is known to be very detrimental to the performance of superconducting quantum devices but the nature of these TLS is still poorly understood. Recent experiments with superconducting resonators indicates that interaction between TLS in the oxide at the film-substrate interface is not negligible. Here we present data on the loss and $1/f$ frequency noise from two different Nb resonators with and without Pt capping and discuss what conclusions can be drawn regarding the properties of TLS in amorphous oxides. We also estimate the concentration and dipole moment of the TLS.

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Jonathan Burnett, Lara Faoro, Tobias Lindstrom. 2015-12-08. Analysis of high quality superconducting resonators: consequences for TLS properties in amorphous oxides. https://doi.org/10.1088/0953-2048%2F29%2F4%2F044008

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