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Diagnosis, prescription and prognosis of a Bell-state filter by quantum process tomography

M. W. Mitchell·C. W. Ellenor·S. Schneider·A. M. Steinberg
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Abstract

Using a Hong-Ou-Mandel interferometer, we apply the techniques of quantum process tomography to characterize errors and decoherence in a prototypical two-photon operation, a singlet-state filter. The quantum process tomography results indicate a large asymmetry in the process and also the required operation to correct for this asymmetry. Finally, we quantify errors and decoherence of the filtering operation after this modification.

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M. W. Mitchell, C. W. Ellenor, S. Schneider, A. M. Steinberg. 2003-04-30. Diagnosis, prescription and prognosis of a Bell-state filter by quantum process tomography. https://doi.org/10.1103/physrevlett.91.120402

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