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arXiv · 1708.00735

Simple factorization of unitary transformations

Hubert de Guise·Olivia Di Matteo·Luis L. Sanchez-Soto
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Abstract

We demonstrate a method for general linear optical networks that allows one to factorize any SU($n$) matrix in terms of two SU($n-1)$ blocks coupled by an SU(2) entangling beam splitter. The process can be recursively continued in an efficient way, ending in a tidy arrangement of SU(2) transformations. The method hinges only on a linear relationship between input and output states, and can thus be applied to a variety of scenarios, such as microwaves, acoustics, and quantum fields.

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Hubert de Guise, Olivia Di Matteo, Luis L. Sanchez-Soto. 2017-08-02. Simple factorization of unitary transformations. https://doi.org/10.1103/physreva.97.022328

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