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Classical Communication Cost in Distributed Quantum Information Processing - A generalization of Quantum Communication Complexity

Hoi-Kwong Lo
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Abstract

We study the amount of classical communication needed for distributed quantum information processing. In particular, we introduce the concept of "remote preparation" of a quantum state. Given an ensemble of states, Alice's task is to help Bob in a distant laboratory to prepare a state of her choice. We find several examples of an ensemble with an entropy S where the remote preparation can be done with a communication cost lower than the amount (2S) required by standard teleportation. We conjecture that, for an arbitrary N-dimensional pure state, its remote preparation requires 2log_2 N bits of classical communication, as in standard teleportation.

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Hoi-Kwong Lo. 2000-04-14. Classical Communication Cost in Distributed Quantum Information Processing - A generalization of Quantum Communication Complexity. https://doi.org/10.1103/physreva.62.012313

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