The superactivation of zero-capacity optical quantum channels makes it possible to use two zero-capacity optical quantum channels with a positive joint capacity at the output. Currently, we have no theoretical results for describing all possible combinations of superactive zero-capacity channels, hence there should be many other possible combinations. This paper shows a fundamentally new method of finding the conditions for the superactivation of the asymptotic Lloyd-Shor-Devetak (LSD) channel capacity of zero-capacity optical quantum channels. We introduce a new geometrical representation, called the quantum informational superball representation. Our method provides a fundamentally new and efficient algorithmic solution for discovering all possible superactive channels and it can be applied to analyze the capacity of these channels.

Date Published: 12 February 2011
PDF: 14 pages
Proc. SPIE 7948, Advances in Photonics of Quantum Computing, Memory, and Communication IV, 79480Q (12 February 2011); doi: 10.1117/12.874185

Published in SPIE Proceedings Vol. 7948:
Advances in Photonics of Quantum Computing, Memory, and Communication IV
Zameer Ul Hasan; Philip R. Hemmer; Hwang Lee; Charles M. Santori, Editor(s)