Quantum state engineering in hybrid open quantum systems

TL;DR

This paper explores generating non-classical, entangled steady states in noisy hybrid light-matter quantum systems, specifically the anisotropic Rabi and Dicke models, and proposes feedback strategies for quantum control.

Contribution

It demonstrates the existence of entangled non-equilibrium steady states in anisotropic Rabi and Dicke models and suggests feedback methods for quantum state protection and control.

Findings

Steady states are mixtures of parity-opposite states with entanglement.

The NESS of the anisotropic Dicke model is also entangled.

Feedback strategies can enhance quantum control in these systems.

Abstract

We investigate a possibility to generate non-classical states in light-matter coupled noisy quantum systems, namely the anisotropic Rabi and Dicke models. In these hybrid quantum systems a competing influence of coherent internal dynamics and environment induced dissipation drives the system into non-equilibrium steady states (NESSs). Explicitly, for the anisotropic Rabi model the steady state is given by an incoherent mixture of two states of opposite parities, but as each parity state displays light-matter entanglement we also find that the full state is entangled. Furthermore, as a natural extension of the anisotropic Rabi model to an infinite spin subsystem, we next explored the NESS of the anisotropic Dicke model. The NESS of this linearized Dicke model is also an inseparable state of light and matter. With an aim to enrich the dynamics beyond the sustainable entanglement found for the NESS of these hybrid quantum systems, we also propose to combine an all-optical feedback strategy for quantum state protection and for establishing quantum control in these systems. Our present work further elucidates the relevance of such hybrid open quantum systems for potential applications in quantum architectures.