We propose a method for preparing maximal path entanglement with a definite photon-number N, larger than two, using projective measurements. In contrast with the previously known schemes, our method uses only linear optics. Specifically, we exhibit a way of generating four-photon, path-entangled states of the form [Formula Presented] using only four beam splitters and two detectors. These states are of major interest as a resource for quantum interferometric sensors as well as for optical quantum lithography and quantum holography. © 2002 The American Physical Society.
Publication Source (Journal or Book title)
Physical Review A - Atomic, Molecular, and Optical Physics
Lee, H., Kok, P., Cerf, N., & Dowling, J. (2002). Linear optics and projective measurements alone suffice to create large-photon-number path entanglement. Physical Review A - Atomic, Molecular, and Optical Physics, 65 (3), 4. https://doi.org/10.1103/PhysRevA.65.030101