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arXiv · 0808.1649

Entangling characterization of (SWAP)1/m and Controlled unitary gates

S. Balakrishnan·R. Sankaranarayanan
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Abstract

We study the entangling power and perfect entangler nature of (SWAP)1/m, for m>=1, and controlled unitary (CU) gates. It is shown that (SWAP)1/2 is the only perfect entangler in the family. On the other hand, a subset of CU which is locally equivalent to CNOT is identified. It is shown that the subset, which is a perfect entangler, must necessarily possess the maximum entangling power.

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S. Balakrishnan, R. Sankaranarayanan. 2009-01-05. Entangling characterization of (SWAP)1/m and Controlled unitary gates. https://doi.org/10.1103/physreva.78.052305

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