Generation of an N-qubit Greenberger-Horne-Zeilinger state with distant atoms in bimodal cavities

A selective photon scheme is proposed to realize an N-qubit Greenberger-Horne-Zeilinger (GHZ) state with distant atoms trapped in spatially separated bimodal cavities coupled by optical fibres. The influence of deviations of some experimental parameters on our scheme is studied exactly and we prove that a highly reliable GHZ state is achievable. Moreover, we analyse the independence of fidelity on decoherence processes, such as atomic spontaneous emission, cavity decay and fibre losses. The results show that atomic spontaneous emission and fibre losses can be ignored in some special cases. With regards to the cavity decay, it indicates that a GHZ state with high fidelity may be realized in the current experiment.