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arXiv · 1304.3693

Bifurcation, mode coupling and noise in a nonlinear multimode superconducting RF resonator

G. Tancredi·G. Ithier·P. J. Meeson
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Abstract

The addition of nonlinearity to an harmonic resonator provides a route to complex dynamical behaviour of resonant modes, including coupling between them. We present a superconducting device that makes use of the nonlinearity of Josephson junctions to introduce a controlled, tunable, nonlinear inductance to a thin film coplanar waveguide resonator. Considering the device as a potential quantum optical component in the microwave regime, we create a sensitive bifurcation amplifier and then demonstrate spectroscopy of other resonant modes via the intermode coupling. We find that the sensitivity of the device approaches within a factor two quantitative agreement with a quantum model by Dykman, but is limited by a noise that has its source(s) on-chip.

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G. Tancredi, G. Ithier, P. J. Meeson. 2013-04-12. Bifurcation, mode coupling and noise in a nonlinear multimode superconducting RF resonator. https://doi.org/10.1063/1.4818123

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