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arXiv · 1908.06341

Implementation of controllable universal unital optical channels

A. Shaham·T. Karni·H. S. Eisenberg
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Abstract

We show that a configuration of four birefringent crystals and wave-plates can emulate almost any arbitrary unital channel for polarization qubits encoded in single photons, where the channel settings are controlled by the wave-plate angles. The scheme is applied to a single spatial mode and its operation is independent of the wavelength and the fine temporal properties of the input light. We implemented the scheme and demonstrated its operation by applying a dephasing environment to classical and quantum single-photon states with different temporal properties. The applied process was characterized by a quantum process tomography procedure, and a high fidelity to the theory was observed.

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A. Shaham, T. Karni, H. S. Eisenberg. 2019-08-17. Implementation of controllable universal unital optical channels. https://doi.org/10.1364/oe.27.023839

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