Spontaneously induced emitter-radiation entanglement due to confinement to photonic band gap

The study of spontaneously induced nonclassicality as a result of the interaction of an ensemble of two-level emitters embedded onto crystal structure embodying photonic band gap (PBG) is presented. The method of coherent-state propagator is applied upon expressing collective atomic operators in terms of boson operators in view of Schwinger's representation. The autocorrelation of photon number of the radiation alone is shown to display super-Poissonian statistics and chaotic photon character. However, the state of the coupled system is found to exhibit entanglement and nonclassical intensity correlation attributed to the confinement, where intensity of the emitted radiation and degree of entanglement are enhanced near the edge. The prospect of embedding emitters onto PBG can hence be taken as a reliable testing ground for examining fundamentals of emitter-radiation interaction and implementing quantum information processing task that requires mapping of stationary memory with flying message.