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arXiv · 1906.10022

Quantum versus classical switching dynamics of driven-dissipative Kerr resonators

Christian Kraglund Andersen·Archana Kamal·Nicholas A. Masluk·Ioan M. Pop·Alexandre Blais·Michel H. Devoret
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Abstract

We report a first-principles study of the driven dissipative dynamics for Kerr oscillators in the mesoscopic regime. This regime is characterized by large Kerr nonlinearity, realized here using the nonlinear kinetic inductance of a large array of Josephson junctions. The experimentally measured nonlinear resonance lineshapes of the junction array modes show significant deviations from steady-state numerical predictions, and necessitate time-dependent numerical simulations indicative of strong measurement-induced dephasing in the system arising from the large cross-Kerr effect between array modes. Analytical and numerical calculations of switching rate corroborate this by showing the emergence of a slow time scale, which is much longer than the linear decay rate and is set by fluctuation-induced switching times in the bistable regime. Furthermore, our analysis shows that the usual quantum-activated escape treatment is inadequate for prediction of the switching rates at large frequency shifts caused by strong nonlinearities, necessitating a quantum treatment that utilizes the full system Liouvillian. Based on our analysis, we identify a universal crossover parameter that delineates the regimes of validity of semiclassical and quantum descriptions, respectively. Our work shows how dynamical switching effects in strongly nonlinear systems provide a platform to study quantum-to-classical transitions.

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Christian Kraglund Andersen, Archana Kamal, Nicholas A. Masluk, Ioan M. Pop, Alexandre Blais, Michel H. Devoret. 2020-04-10. Quantum versus classical switching dynamics of driven-dissipative Kerr resonators. https://doi.org/10.1103/physrevapplied.13.044017

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