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arXiv · 1707.04093

Period-tripling subharmonic oscillations in a driven superconducting resonator

Ida-Maria Svensson·Andreas Bengtsson·Philip Krantz·Jonas Bylander·Vitaly Shumeiko·Per Delsing
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Abstract

We have observed period-tripling subharmonic oscillations, in a superconducting coplanar waveguide resonator operated in the quantum regime, $k_B T \ll \hbarω$. The resonator is terminated by a tunable inductance that provides a Kerr-type nonlinearity. We detected the output field quadratures at frequencies near the fundamental mode, $ω/2π\sim 5\,$GHz, when the resonator was driven by a current at $3ω$ with an amplitude exceeding an instability threshold. The output radiation was red-detuned from the fundamental mode. We observed three stable radiative states with equal amplitudes and phase-shifted by $120^\circ$. The downconversion from $3ω$ to $ω$ is strongly enhanced by resonant excitation of the second mode of the resonator, and the cross-Kerr effect. Our experimental results are in quantitative agreement with a model for the driven dynamics of two coupled modes.

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Ida-Maria Svensson, Andreas Bengtsson, Philip Krantz, Jonas Bylander, Vitaly Shumeiko, Per Delsing. 2017-11-09. Period-tripling subharmonic oscillations in a driven superconducting resonator. https://doi.org/10.1103/physrevb.96.174503

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