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arXiv · 1510.00606

Constructive quantum scaling of unitary matrices

Adam Glos·Przemysław Sadowski
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Abstract

In this work we present a method of decomposition of arbitrary unitary matrix $U\in\mathbf U(2^k)$ into a product of single-qubit negator and controlled-$\sqrt{\mbox{NOT}}$ gates. Since the product results with negator matrix, which can be treated as complex analogue if bistochastic matrix, our method can be seen as complex analogue of Sinkhorn-Knopp algorithm, where diagonal matrices are replaced by adding and removing an one-qubit ancilla. The decomposition can be found constructively and resulting circuit consists of $O(4^k)$ entangling gates, which is proved to be optimal. An example of such transformation is presented.

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Adam Glos, Przemysław Sadowski. 2016-10-26. Constructive quantum scaling of unitary matrices. https://doi.org/10.1007/s11128-016-1448-z

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