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arXiv · 0711.4021

How many CNOT gates does it take to generate a three-qubit state ?

Marko Znidaric·Olivier Giraud·Bertrand Georgeot
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Abstract

The number of two-qubit gates required to transform deterministically 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 GHZ 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.

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Marko Znidaric, Olivier Giraud, Bertrand Georgeot. 2007-11-26. How many CNOT gates does it take to generate a three-qubit state ?. https://doi.org/10.1103/physreva.77.032320

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