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Probabilistic Quantum Encoder for Single-Photon Qubits

T. B. Pittman·B. C Jacobs·J. D. Franson
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Abstract

We 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, post-selection, 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.

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T. B. Pittman, B. C Jacobs, J. D. Franson. 2003-12-10. Probabilistic Quantum Encoder for Single-Photon Qubits. https://doi.org/10.1103/physreva.69.042306

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