Pittman, T.B.Jacobs, B. C.Franson, J.D.2020-08-032020-08-032004-04-14T. B. Pittman, B. C Jacobs, and J. D. Franson, Probabilistic quantum encoder for single-photon qubits, Phys. Rev. A 69, 042306 (2004), DOI:https://doi.org/10.1103/PhysRevA.69.042306https://doi.org/10.1103/PhysRevA.69.042306http://hdl.handle.net/11603/19309We describe an experiment in which a physical qubit represented by the polarization state of a single photon was probabilistically encoded in the logical state of two photons. The experiment relied on linear optics, postselection, and three-photon interference effects produced by a parametric down-conversion photon pair and a weak coherent state. An interesting consequence of the encoding operation was the ability to observe entangled three-photon Greenberger-Horne-Zeilinger states.4 pagesen-USThis item is likely protected under Title 17 of the U.S. Copyright Law. Unless on a Creative Commons license, for uses protected by Copyright Law, contact the copyright holder or the author.©2004 The American Physical SocietyText