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arXiv · 1307.2498

Universal quantum fluctuations of a cavity mode driven by a Josephson junction

A. D. Armour·M. P. Blencowe·E. Brahimi·A. J. Rimberg
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Abstract

We analyze the quantum dynamics of a superconducting cavity coupled to a voltage biased Josephson junction. The cavity is strongly excited at resonances where the voltage energy lost by a Cooper pair traversing the circuit is a multiple of the cavity photon energy. We find that the resonances are accompanied by substantial squeezing of the quantum fluctuations of the cavity over a broad range of parameters and are able to identify regimes where the fluctuations in the system take on universal values.

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A. D. Armour, M. P. Blencowe, E. Brahimi, A. J. Rimberg. 2013-07-09. Universal quantum fluctuations of a cavity mode driven by a Josephson junction. https://doi.org/10.1103/physrevlett.111.247001

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