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.
@article{arxiv.1207.5487,
title = {Nonlocal Interferometry Using Macroscopic Coherent States and Weak Nonlinearities},
author = {B. T. Kirby and J. D. Franson},
journal= {arXiv preprint arXiv:1207.5487},
year = {2015}
}