Entanglement and disentanglement in circuit QED architectures

We propose a protocol for creating entanglement within a dissipative circuit QED network architecture that consists of two electromagnetic circuits (cavities) and two superconducting qubits. The system interacts with a quantum environment, giving rise to decoherence and dissipation. We discuss the preparation of two separate entangled cavity-qubit states via Landau-Zener sweeps, after which the cavities interact through mechanical a tunable "quantum switch" which is realized with an ancilla qubit. Moreover, we discuss the decay of the resulting entangled two-cavity state due to the influence of the environment, where we focus on the entanglement decay. (C) 2009 Elsevier B.V. All rights reserved.