GHZ state generation of three Josephson qubits in the presence of bosonic baths

We analyse an entangling protocol to generate tripartite Greenberger–Horne–Zeilinger (GHZ) states in a system consisting of three superconducting qubits with pairwise coupling. The dynamics of the open quantum system is investigated by taking into account the interaction of each qubit with an independent bosonic bath with an ohmic spectral structure. To this end, a microscopic master equation is constructed and exactly solved. We find that the protocol discussed here is stable against decoherence and dissipation due to the presence of the external baths.