Asymptotically optimal quantum channel reversal for qudit ensembles and multimode Gaussian states

Bowles, P.; Gu??, M.; Adesso, Gerardo

Abstract

We investigate the problem of optimally reversing the action of an arbitrary quantum channel C which acts independently on each component of an ensemble of n identically prepared d-dimensional quantum systems. In the limit of large ensembles, we construct the optimal reversing channel R☆n which has to be applied at the output ensemble state, to retrieve a smaller ensemble of m systems prepared in the input state, with the highest possible rate m/n. The solution is found by mapping the problem into the optimal reversal of Gaussian channels on multimode quantum-classical continuous variable systems, which is solved here as well. Our general results can be readily applied to improve the implementation of robust long-distance quantum communication. As an example, we investigate the optimal reversal rate of phase flip channels acting on a multi-qubit register.

Citation

Bowles, P., Guţă, M., & Adesso, G. (2012). Asymptotically optimal quantum channel reversal for qudit ensembles and multimode Gaussian states. New Journal of Physics, 14, Article 113041. https://doi.org/10.1088/1367-2630/14/11/113041

• Journal Article Type: Article
• Publication Date: Nov 29, 2012
• Deposit Date: Apr 1, 2014
• Publicly Available Date: Apr 1, 2014
• Journal: New Journal of Physics
• Electronic ISSN: 1367-2630
• Publisher: IOP Publishing
• Peer Reviewed: Peer Reviewed
• Volume: 14
• Article Number: 113041
• DOI: https://doi.org/10.1088/1367-2630/14/11/113041
• Public URL: https://nottingham-repository.worktribe.com/output/712040
• Publisher URL: http://iopscience.iop.org/1367-2630/14/11/113041/