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arXiv · 1008.1128

Entanglement cost of implementing controlled-unitary operations

Akihito Soeda·Peter S. Turner·Mio Murao
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Abstract

We investigate the minimum entanglement cost of the deterministic implementation of two-qubit controlled-unitary operations using local operations and classical communication (LOCC). We show that any such operation can be implemented by a three-turn LOCC protocol, which requires at least 1 ebit of entanglement when the resource is given by a bipartite entangled state with Schmidt number 2. Our result implies that there is a gap between the minimum entanglement cost and the entangling power of controlled-unitary operations. This gap arises due to the requirement of implementing the operations while oblivious to the identity of the inputs.

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Akihito Soeda, Peter S. Turner, Mio Murao. 2011-10-27. Entanglement cost of implementing controlled-unitary operations. https://doi.org/10.1103/physrevlett.107.180501

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