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Polarization ququarts

Yu. I. Bogdanov·E. V. Moreva·G. A. Maslennikov·R. F. Galeev·S. S. Straupe·S. P. Kulik
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Abstract

We discuss the concept of polarization states of four-dimensional quantum systems based on frequency non-degenerate biphoton field. Several quantum tomography protocols were developed and implemented for measurement of an arbitrary state of ququart. A simple method that does not rely on interferometric technique is used to generate and measure the sequence of states that can be used for quantum communication purposes.

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Yu. I. Bogdanov, E. V. Moreva, G. A. Maslennikov, R. F. Galeev, S. S. Straupe, S. P. Kulik. 2006-02-16. Polarization ququarts. https://doi.org/10.1103/physreva.73.063810

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