Communication Enhancement through Quantum Coherent Control of N Channels in an Indefinite Causal-Order Scenario

Entropy

LorenzoM. Procopio¹  Nadia Belabas¹  JuanAriel Levenson¹  Marco Enríquez²  Francisco Delgado² 

[1] Centre for Nanoscience and Nanotechnology, C2N, CNRS, Université Paris-Sud, Université Paris-Saclay, 91120 Palaiseau, France;Tecnologico de Monterrey, School of Engineering and Science, Atizapán, México 52926, Mexico;

关键词: quantum control;    indefinite causal order;    quantum switch;    holevo information;   

DOI  :  10.3390/e21101012

来源: DOAJ

【 摘 要 】

In quantum Shannon theory, transmission of information is enhanced by quantum features. Up to very recently, the trajectories of transmission remained fully classical. Recently, a new paradigm was proposed by playing quantum tricks on two completely depolarizing quantum channels i.e., using coherent control in space or time of the two quantum channels. We extend here this control to the transmission of information through a network of an arbitrary number N of channels with arbitrary individual capacity i.e., information preservation characteristics in the case of indefinite causal order. We propose a formalism to assess information transmission in the most general case of N channels in an indefinite causal order scenario yielding the output of such transmission. Then, we explicitly derive the quantum switch output and the associated Holevo limit of the information transmission for $N=2$ , $N=3$ as a function of all involved parameters. We find in the case $N=3$ that the transmission of information for three channels is twice that of transmission of the two-channel case when a full superposition of all possible causal orders is used.

【 授权许可】

Unknown