Generation of cluster-type entangled coherent states using weak nonlinearities

Abstract

We propose a scheme to generate a recently introduced type of entangled coherent states using realistic weak cross-Kerr nonlinearities and intense laser beams. An intense laser can be filtered to make a faint one to be used for production of a single photon which is necessary in our scheme. The optical devices used are conventional ones such as interferometer, mirrors, beam-splitters, phase-shifters and photo-detectors. We also provide a detailed analysis on the effects of possible imperfections and decoherence showing that our scheme is robust against such effects.