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arXiv · 2303.13645

More assistance of entanglement, less rounds of classical communication

Atanu Bhunia·Indranil Biswas·Indrani Chattopadhyay·Debasis Sarkar
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Abstract

Classical communication plays a crucial role to distinguish locally a class of quantum states. Despite considerable advances, we have very little knowledge about the number of measurement and communication rounds needed to implement a discrimination task by local quantum operations and classical communications (in short, LOCC). In this letter, we are able to show the relation between round numbers with the local discrimination of a set of pure bipartite orthogonal quantum states. To demonstrate the possible strong dependence on the round numbers, we consider a class of orthogonal product states in $d\otimes d$, which require at least $2d-2$ round of classical communications. Curiously the round number can be reduced to $d$ by the assistance of one-ebit of entanglement as resource and can be reduced further by assistance of more entanglement. We are also able to show that the number of LOCC rounds needed for a discrimination task may depend on the amount of entanglement assistances.

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Atanu Bhunia, Indranil Biswas, Indrani Chattopadhyay, Debasis Sarkar. 2023-03-23. More assistance of entanglement, less rounds of classical communication. https://doi.org/10.1088/1751-8121/aceddb

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