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arXiv:0804.3327 · Physical Review A

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

So-Young Baek, Stanislav S. Straupe, Alexander P. Shurupov, S. P. Kulik, Yoon-Ho Kim

Published Oct 22, 2008• 43 citations
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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 mixed state (fully diagonal), and a mixed state (partially coherent), are experimentally demonstrated.

DOI
10.1103/physreva.78.042321

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