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Inefficiency and classical communication bounds for conversion between partially entangled pure bipartite states

Ben Fortescue·Hoi-Kwong Lo
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Abstract

We derive lower limits on the inefficiency and classical communication costs of dilution between two-term bipartite pure states that are partially entangled. We first calculate explicit relations between the allowable error and classical communication costs of entanglement dilution using the protocol of Lo-Popescu and then consider a two-stage dilution from singlets with this protocol followed by some unknown protocol for conversion between partially entangled states. Applying the lower bounds on classical communication and inefficiency of Harrow-Lo and Hayden-Winter to this two-stage protocol, we derive bounds for the unknown protocol. In addition we derive analogous (but looser) bounds for general pure states.

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Ben Fortescue, Hoi-Kwong Lo. 2006-07-20. Inefficiency and classical communication bounds for conversion between partially entangled pure bipartite states. https://doi.org/10.1103/physreva.72.032336

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