Physical Review Letters
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.
Armour, A. D.; Blencowe, M. P.; Brahimi, E.; and Rimberg, A. J., "Universal Quantum Fluctuations of a Cavity Mode Driven by a Josephson Junction" (2013). Open Dartmouth: Faculty Open Access Articles. 3521.