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arXiv · 0804.3327

Preparation and characterization of arbitrary states of four-dimensional qudits based on biphotons

So-Young Baek·Stanislav S. Straupe·Alexander P. Shurupov·Sergei P. Kulik·Yoon-Ho Kim
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Abstract

We report interferometric schemes to prepare arbitrary states of four-dimensional qudits (ququarts) based on biphoton states of ultrafast-pumped frequency-nondegenerate spontaneous parametric down-conversion. Preparation and tomographic characterization of a few examples of general single-ququart states, a pure state, a completely mixed state, and a partially-mixed state, are experimentally demonstrated.

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So-Young Baek, Stanislav S. Straupe, Alexander P. Shurupov, Sergei P. Kulik, Yoon-Ho Kim. 2008-04-21. Preparation and characterization of arbitrary states of four-dimensional qudits based on biphotons. https://doi.org/10.1103/physreva.78.042321

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