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arXiv:1307.2498 · Physical Review Letters

Universal Quantum Fluctuations of a Cavity Mode Driven by a Josephson Junction

Andrew D. Armour, M. P. Blencowe, Erind Brahimi, A. J. Rimberg

Published Dec 9, 2013• 75 citations
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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.

DOI
10.1103/physrevlett.111.247001

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