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arXiv · 2012.02233

Critical fluorescence of a transmon at the Schmid transition

M. Houzet·L. I. Glazman
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Abstract

We investigate inelastic microwave photon scattering by a transmon qubit embedded in a high-impedance circuit. The transmon undergoes a charge-localization (Schmid) transition upon the impedance reaching the critical value. Due to the unique transmon level structure, the fluorescence spectrum carries a signature of the transition point. At higher circuit impedance, quasielastic photon scattering may account for the main part of the inelastic scattering cross-section; we find its dependence on the qubit and circuit parameters.

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M. Houzet, L. I. Glazman. 2020-12-03. Critical fluorescence of a transmon at the Schmid transition. https://doi.org/10.1103/physrevlett.125.267701

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