Nonequilibrium dynamics of the Jaynes-Cummings dimer

TL;DR

This paper explores the complex nonequilibrium behavior of a Josephson-coupled Jaynes-Cummings dimer with Kerr nonlinearity, revealing diverse dynamical regimes, quantum effects, and potential applications in quantum information processing.

Contribution

It provides a comprehensive analysis of both semiclassical and quantum dynamics of the system, highlighting new phenomena like quantum revivals, entanglement, and phase space mixing under quenches.

Findings

Identification of various photonic Josephson oscillations and stability regimes.

Observation of quantum effects such as spin dephasing, phase fluctuations, and revivals.

Correlation between mutual information and photon population imbalance in self-trapped states.

Abstract

We investigate the nonequilibrium dynamics of a Josephson-coupled Jaynes-Cummings dimer in the presence of Kerr nonlinearity, which can be realized in the cavity and circuit quantum electrodynamics systems. The semiclassical dynamics is analyzed systematically to chart out a variety of photonic Josephson oscillations and their regime of stability. Different types of transitions between the dynamical states lead to the self-trapping phenomenon, which results in photon population imbalance between the two cavities. We also study the dynamics quantum mechanically to identify characteristic features of different steady states and to explore fascinating quantum effects, such as spin dephasing, phase fluctuation, and revival phenomena of the photon field, as well as the entanglement of spin qubits. For a particular "self-trapped" state, the mutual information between the atomic qubits exhibits a direct correlation with the photon population imbalance, which is promising for generating photon mediated entanglement between two non interacting qubits in a controlled manner. Under a sudden quench from stable to unstable regime, the photon distribution exhibits phase space mixing with a rapid loss of coherence, resembling a thermal state. Finally, we discuss the relevance of the new results in experiments, which can have applications in quantum information processing and quantum technologies.