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arXiv:0711.4021 · Physical Review A

Optimal number of controlled-NOT gates to generate a three-qubit state

Marko Žnidarič, Olivier Giraud, Bertrand Georgeot

Published Mar 13, 2008• 30 citations
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Abstract

The number of two-qubit gates required to deterministically transform a three-qubit pure quantum state into another is discussed. We show that any state can be prepared from a product state using at most three CNOT gates and that starting from the Greenberger-Horne-Zeilinger state, only two suffice. As a consequence, any three-qubit state can be transformed into any other using at most four CNOT gates. Generalizations to other two-qubit gates are also discussed.

DOI
10.1103/physreva.77.032320

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