Nonlocal Interferometry Using Macroscopic Coherent States and Weak   Nonlinearities
  A method for performing nonlocal interferometry using phase-entangled macroscopic coherent states is described. The required entanglement can be generated using weak nonlinearities while Bell's inequality can be violated using single photons as a probe. The entanglement is relatively robust against photon loss and Bell's inequality can be violated over a relatively large distance in optical fibers despite the fact that a large number of photons are absorbed in the process. 
B. T. Kirby and J. D. Franson
quant-ph