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arXiv · 1912.09796

Nonadiabatic holonomic multiqubit controlled gates

P. Z. Zhao·G. F. Xu·D. M. Tong
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Abstract

Previous schemes of nonadiabatic holonomic quantum computation were focused mainly on realizing a universal set of elementary gates. Multiqubit controlled gates could be built by decomposing them into a series of the universal gates. In this article, we propose an approach for realizing nonadiabatic holonomic multiqubit controlled gates in which a $(n+1)$-qubit controlled-$(\boldsymbol{\mathrm{n}\cdot \mathrm{\sigma}})$ gate is realized by $(2n-1)$ basic operations instead of decomposing it into the universal gates, whereas an $(n+1)$-qubit controlled arbitrary rotation gate can be obtained by combining only two such controlled-$(\boldsymbol{\mathrm{n}\cdot \mathrm{\sigma}})$ gates. Our scheme greatly reduces the operations of nonadiabatic holonomic quantum computation.

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P. Z. Zhao, G. F. Xu, D. M. Tong. 2019-12-20. Nonadiabatic holonomic multiqubit controlled gates. https://doi.org/10.1103/physreva.99.052309

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