Entanglement Swapping of Bright EPR Optical Beams
Jing Zhang · Acta Sinica Quantum Optica · 2002
A scheme achieving quantum entanglement swapping between two pairs of bright EPR optical beams is theoretically proposed. Two pairs of coherent EPR beams are produced from two independent nondegenerate optical parametric amplifiers. The entanglement swapping is demonstrated by means of a half of each EPR beam. The measuring process entangles other two halves of EPR beams that have never directly interacted with each other. In the proposed system, the direct detection of Bell-states is applied instead of usual homodyne detetion. Due to that the local oscillator is not needed, the technic trouble for mode-matching is overcome and the efficiency of the detection can be increased in experiments.