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Title: Channel activation of CHSH nonlocality
Abstract

Quantum channels that break CHSH nonlocality on all input states are known as CHSH-breaking channels. In quantum networks, such channels are useless for distributing correlations that can violate the CHSH Inequality. Motivated by previous work on activation of nonlocality in quantum states, here we demonstrate an analogous activation of CHSH-breaking channels. That is, we show that certain pairs of CHSH-breaking channels are no longer CHSH-breaking when used in combination. We find that this type of activation can emerge in both uni-directional and bi-directional communication scenarios.

 
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Award ID(s):
1839177
NSF-PAR ID:
10303256
Author(s) / Creator(s):
; ; ;
Publisher / Repository:
IOP Publishing
Date Published:
Journal Name:
New Journal of Physics
Volume:
22
Issue:
4
ISSN:
1367-2630
Page Range / eLocation ID:
Article No. 043003
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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