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arXiv · 1410.7785

Light-matter decoupling and $A^2$ term detection in superconducting circuits

Juan José García-Ripoll·Borja Peropadre·Simone De Liberato
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Abstract

We study the spontaneous emission of a qubit interacting with a one-dimensional waveguide through a realistic minimal-coupling interaction. We show that the diamagnetic term $A^2$ leads to an effective decoupling of a single qubit from the electromagnetic field. This effects is observable at any range of qubit-photon couplings. For this we study a setup consisting of a transmon that is suspended over a transmission line. We prove that the relative strength of the $A^2$ term is controlled with the qubit-line separation and show that, as a consequence, the spontaneous emission rate of the suspended transmon onto the line can increase with such separation, instead of decreasing.

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Juan José García-Ripoll, Borja Peropadre, Simone De Liberato. 2014-10-28. Light-matter decoupling and $A^2$ term detection in superconducting circuits. https://doi.org/10.1038/srep16055

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