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Improved Quantum Cost for n-bit Toffoli Gates

Dmitri Maslov·Gerhard W. Dueck
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Abstract

We present an n-bit Toffoli gate quantum circuit based on the realization proposed by Barenco, where some of the Toffoli gates in their construction are replaced with Peres gates. This results in a significant cost reduction. Our main contribution is a quantum circuit which simulates the (m+1)-bit Toffoli gate with 32m-96 elementary quantum gates and one garbage bit which is passed unchanged. This paper is a corrected and expanded version of our recent journal publication.

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Dmitri Maslov, Gerhard W. Dueck. 2004-03-05. Improved Quantum Cost for n-bit Toffoli Gates. https://doi.org/10.1049/el%3A20031202

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