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arXiv · 1905.08080

Characterization of Depolarizing Channels Using Two-Photon Intereference

Gustavo C. Amaral·Guilherme P. Temporão
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Abstract

Depolarization is one of the most important sources of error in a quantum communication link that can be introduced by the quantum channel. Even though standard quantum process tomography can, in theory, be applied to characterize this effect, in most real-world implementations depolarization cannot be distinguished from time-varying unitary transformations, especially when the time scales are much shorter than the detectors response time. In this paper, we introduce a method for distinguishing true depolarization from fast polarization rotations by employing Hong-Ou-Mandel interference. It is shown that the results are independent of the timing resolutions of the photodetectors.

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Gustavo C. Amaral, Guilherme P. Temporão. 2019-05-20. Characterization of Depolarizing Channels Using Two-Photon Intereference. https://arxiv.org/abs/1905.08080

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