Quantum superposition of the order of parties as a communication resource

Author(s)
Adrien Feix, Mateus Araújo, Caslav Brukner
Abstract

In a variant of communication complexity tasks, two or more separated parties cooperate to compute a function of their local data, using a limited amount of communication. It is known that communication of quantum systems and shared entanglement can increase the probability for the parties to arrive at the correct value of the function, compared to classical resources. Here we show that quantum superpositions of the direction of communication between parties can also serve as a resource to improve the probability of success. We present a tripartite task for which such a superposition provides an advantage compared to the case where the parties communicate in a fixed order. In a more general context, our result also provides semi-device-independent certification of the absence of a definite order of communication.

Organisation(s)
Quantum Optics, Quantum Nanophysics and Quantum Information
External organisation(s)
Österreichische Akademie der Wissenschaften (ÖAW)
Journal
Physical Review A
Volume
92
No. of pages
5
ISSN
1050-2947
Publication date
11-2015
Peer reviewed
Yes
Austrian Fields of Science 2012
103025 Quantum mechanics
ASJC Scopus subject areas
Atomic and Molecular Physics, and Optics
Portal url
https://ucrisportal.univie.ac.at/en/publications/6ea81209-ffd4-48f8-b9ed-89c7de9386f6