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arXiv · 1505.03297

Experimental quantum tomography of a homodyne detector

Samuele Grandi·Alessandro Zavatta·Marco Bellini·Matteo G. A. Paris
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Abstract

We suggest and demonstrate a tomographic method to fully characterize homodyne detectors at the quantum level. The operator measure associated with the detector is expanded in the quadrature basis and probed with a set of coherent states. The coefficients of the expansion are retrieved using a least squares algorithm. We then validate the reconstructed operator measure on nonclassical states. Finally, we exploit results to estimate the overall quantum efficiency of the detector.

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Samuele Grandi, Alessandro Zavatta, Marco Bellini, Matteo G. A. Paris. 2015-05-13. Experimental quantum tomography of a homodyne detector. https://doi.org/10.1088/1367-2630%2Faa6f2c

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