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arXiv · 2012.15459

Random-Receiver Quantum Communication

Some Sankar Bhattacharya·Ananda G. Maity·Tamal Guha·Giulio Chiribella·Manik Banik
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Abstract

We introduce the task of random-receiver quantum communication, in which a sender transmits a quantum message to a receiver chosen from a list of n spatially separated parties. The choice of receiver is unknown to the sender, but is known by the n parties, who coordinate their actions by exchanging classical messages. In normal conditions, random-receiver quantum communication requires a noiseless quantum communication channel from the sender to each of the n receivers. In contrast, we show that random-receiver quantum communication can take place through entanglement-breaking channels if the order of such channels is controlled by a quantum bit that is accessible through quantum measurements. Notably, this phenomenon cannot be mimicked by allowing free quantum communication between the sender and any subset of k<n parties.

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Some Sankar Bhattacharya, Ananda G. Maity, Tamal Guha, Giulio Chiribella, Manik Banik. 2020-12-31. Random-Receiver Quantum Communication. https://doi.org/10.1103/prxquantum.2.020350

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