Engineering distributed atomic NOON states via single-photon detection

Abstract

We propose a simple and novel scheme to generate a NOON state for the atoms trapped in two separate cavities by means of single-photon detection. The light–atom interaction entangles the frequency spectrum of light and the atomic collective spins, and the photon–atom entangled state is converted to a purely atomic NOON state by time-resolved detection on the transmitted photon. The fidelity of the NOON state reduces in the presence of dissipation. We further propose an effective protocol to improve the fidelity, which yields a high-fidelity many-atom NOON state. Our scheme can be implemented with the current technology.