Tripartite entanglement in parametric down-conversion with spatially structured pump
D. Daems, F. Bernard, Nicolas J. Cerf, Mikhail I. Kolobov · Journal of the Optical Society of America B · 2010
Most investigations of multipartite entanglement have been concerned with temporal modes of the electromagnetic field and have neglected its spatial structure. We present a simple model which allows us to generate tripartite entanglement between spatial modes by parametric down-conversion with two symmetrically tilted plane waves serving as a pump. The characteristics of this entanglement are investigated. We also discuss the generalization of our scheme to 2N+1 partite entanglement using 2N symmetrically tilted plane pump waves. Another interesting feature is the possibility of entanglement localization in just two spatial modes.