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Experimental realization of entangled qutrits for quantum communication

R. T. Thew·A. Acin·H. Zbinden·N. Gisin
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Abstract

We have experimentally realized a technique to generate, control and measure entangled qutrits, 3-dimensional quantum systems. This scheme uses spontaneous parametric down converted photons and unbalanced 3-arm fiber optic interferometers in a scheme analogous to the Franson interferometric arrangement for qubits. The results reveal a source capable of generating maximally entangled states with a net state fidelity, F = 0.985 $\pm$ 0.018. Further the control over the system reveals a high, net, 2-photon interference fringe visibility, V = 0.919 $\pm$ 0.026. This has all been done at telecom wavelengths thus facilitating the advancement towards long distance higher dimensional quantum communication.

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R. T. Thew, A. Acin, H. Zbinden, N. Gisin. 2004-02-05. Experimental realization of entangled qutrits for quantum communication. https://arxiv.org/abs/quant-ph/0307122

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