Entanglement creation and distribution on a graph of exchange-coupled   qutrits
  We propose a protocol that allows both the creation and distribution of entanglement, resulting in two distant parties (Alice and Bob) conclusively sharing a bipartite Bell State. The system considered is a graph of three-level objects ("qutrits") coupled by SU(3) exchange operators. The protocol begins with a third party (Charlie) encoding two lattice sites in unentangled states, and allowing unitary evolution under time. Alice and Bob perform a projective measurement on their respective qutrits at a given time, and obtain a maximally-entangled Bell state with a certain probablility. We also consider two further protocols, one based on simple repetition and the other based on successive measurements and conditional resetting, and show that the cumulative probability of creating a Bell state between Alice and Bob tends to unity. 
Christopher Hadley, Alessio Serafini and Sougato Bose