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arXiv · 0707.3728

Fiber-optic realization of anisotropic depolarizing quantum channels

Michal Karpinski·Czeslaw Radzewicz·Konrad Banaszek
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Abstract

We employed an electrically-driven polarization controller to implement anisotropic depolarizing quantum channels for the polarization state of single photons. The channels were characterized by means of ancilla-assisted quantum process tomography using polarization-entangled photons generated in the process of spontaneous parametric down-conversion. The demonstrated depolarization method offers good repeatability, low cost, and compatibility with fiber-optic setups. It does not perturb the modal structure of single photons, and therefore can be used to verify experimentally protocols for managing decoherence effects based on multiphoton interference.

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Michal Karpinski, Czeslaw Radzewicz, Konrad Banaszek. 2007-07-25. Fiber-optic realization of anisotropic depolarizing quantum channels. https://doi.org/10.1364/josab.25.000668

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