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arXiv · 2004.07710

Quantum circuit synthesis using Householder transformations

Timothée Goubault de Brugière·Marc Baboulin·Benoît Valiron·Cyril Allouche
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Abstract

The synthesis of a quantum circuit consists in decomposing a unitary matrix into a series of elementary operations. In this paper, we propose a circuit synthesis method based on the QR factorization via Householder transformations. We provide a two-step algorithm: during the first step we exploit the specific structure of a quantum operator to compute its QR factorization, then the factorized matrix is used to produce a quantum circuit. We analyze several costs (circuit size and computational time) and compare them to existing techniques from the literature. For a final quantum circuit twice as large as the one obtained by the best existing method, we accelerate the computation by orders of magnitude.

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Timothée Goubault de Brugière, Marc Baboulin, Benoît Valiron, Cyril Allouche. 2020-04-16. Quantum circuit synthesis using Householder transformations. https://doi.org/10.1016/j.cpc.2019.107001

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