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DOE OSTI · 1624519

Degree of Quantumness in Quantum Synchronization

Eneriz, H.·Rossatto, D. Z.·Cárdenas-López, F. A.·Solano, E.·Sanz, M.
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Abstract

We introduce the concept of degree of quantumness in quantum synchronization, a measure of the quantum nature of synchronization in quantum systems. Following techniques from quantum information, we propose the number of non-commuting observables that synchronize as a measure of quantumness. This fgure of merit is compatible with already existing synchronization measurements, and it captures diferent physical properties. We illustrate it in a quantum system consisting of two weakly interacting cavity-qubit systems, which are coupled via the exchange of bosonic excitations between the cavities. Moreover, we study the synchronization of the expectation values of the Pauli operators and we propose a feasible superconducting circuit setup. Finally, we discuss the degree of quantumness in the synchronization between two quantum van der Pol oscillators.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS97 MATHEMATICS AND COMPUTINGQuantum informationSuperconducting devices

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Eneriz, H., Rossatto, D. Z., Cárdenas-López, F. A., Solano, E., Sanz, M.. 2019-12-27. Degree of Quantumness in Quantum Synchronization. https://doi.org/10.1038/s41598-019-56468-x

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