Generation of multiphoton entanglement by propagation and detection
Hoda Hossein-Nejad, R. Stock, Daniel F. V. James · Physical Review A · 2009
We investigate the change in entanglement of photons due to propagation and postselection. We find that postselected entanglement varies by propagation and that states with maximum bipartite and tripartite entanglement can be generated from propagation of unentangled photons. We generalize the results to $n$ photons and show that entangled states with permutation symmetry can be generated from propagation of unentangled states. We discuss the creation of $n$-photon Greenberger-Horne-Zeilinger states as an example of a class of states with the desired symmetry.