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Relations for classical communication capacity and entanglement capability of two-qubit operations

Dominic W. Berry·Barry C. Sanders
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Abstract

Bipartite operations underpin both classical communication and entanglement generation. Using a superposition of classical messages, we show that the capacity of a two-qubit operation for error-free entanglement-assisted bidirectional classical communication can not exceed twice the entanglement capability. In addition we show that any bipartite two-qubit operation can increase the communication that may be performed using an ensemble by twice the entanglement capability.

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Dominic W. Berry, Barry C. Sanders. 2002-11-29. Relations for classical communication capacity and entanglement capability of two-qubit operations. https://doi.org/10.1103/physreva.67.040302

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