We propose schemes for generating multiple-atom entangled states and a multiple-photon Greenberger-Horne-Zeilinger state, respectively, based on the input-output relation of the cavity. The numerical simulations show that produced multiple-particle entangled states have high fidelity even if the atoms are not localized in the Lamb-Dicke regime. Some practical quantum noises, such as atomic spontaneous emission and output coupling inefficiency, only decrease the success probability but exert no influence on the fidelity of prepared multiple-particle entangled states. The successful probabilities of our protocols approach unity in the ideal case. In addition, no need for individually addressing keeps the schemes easy to implement from the experimental point of view.

• Received 29 September 2006

DOI:https://doi.org/10.1103/PhysRevA.74.052339