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arXiv · quant-ph/0312135

Homodyne tomography characterization and nonlocality of a dual-mode optical qubit

S. A. Babichev·J. Appel·A. I. Lvovsky
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Abstract

A single photon, delocalized over two optical modes, is characterized by means of quantum homodyne tomography. The reconstructed four-dimensional density matrix extends over the entire Hilbert space and thus reveals, for the first time, complete information about the dual-rail optical quantum bit as a state of the electromagnetic field. The experimental data violate the Bell inequality albeit with a loophole similar to the detection loophole in photon counting experiments.

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S. A. Babichev, J. Appel, A. I. Lvovsky. 2004-03-16. Homodyne tomography characterization and nonlocality of a dual-mode optical qubit. https://doi.org/10.1103/physrevlett.92.193601

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