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arXiv · 1610.07461

Role of qubit-cavity entanglement for switching dynamics of quantum interfaces in superconductor metamaterials

Sergey V. Remizov·Dmitriy S. Shapiro·Alexey N. Rubtsov
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Abstract

We study quantum effects of strong driving field applied to dissipative hybrid qubit-cavity system which are relevant for a realization of quantum gates in superconducting quantum metamaterials. We demonstrate that effects of strong and non-stationary drivings have significantly quantum nature and can not be treated by means of mean-field approximation. This is shown from a comparison of steady state solution of the standard Maxwell-Bloch equations and numerical solution of Lindblad equation on a density matrix. We show that mean-field approach provides very good agreement with the density matrix solution at not very strong drivings $f f^*$ a growing value of quantum correlations between fluctuations in qubit and photon sectors changes a behavior of the system. We show that in regime of non-adiabatic switching on of the driving such a quantum correlations influence a dynamics of qubit and photons even at weak $f$.

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Sergey V. Remizov, Dmitriy S. Shapiro, Alexey N. Rubtsov. 2016-10-24. Role of qubit-cavity entanglement for switching dynamics of quantum interfaces in superconductor metamaterials. https://doi.org/10.1134/s0021364017020060

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