No-activation theorem for Gaussian nonclassical correlations by Gaussian operations

Mi�ta, Ladislav; McNulty, Daniel; Adesso, Gerardo

Abstract

We study general quantum correlations of continuous variable Gaussian states and their interplay with entanglement. Specifically, we investigate the existence of a quantum protocol activating all nonclassical correlations between the subsystems of an input bipartite continuous variable system, into output entanglement between the system and a set of ancillae. For input Gaussian states, we prove that such an activation protocol cannot be accomplished with Gaussian operations, as the latter are unable to create any output entanglement from an initial separable yet nonclassical state in a worst-case scenario. We then construct a faithful non-Gaussian activation protocol, encompassing infinite-dimensional generalizations of controlled-not gates to generate entanglement between system and ancillae, in direct analogy with the finite-dimensional case. We finally calculate the negativity of quantumness, an operational measure of nonclassical correlations defined in terms of the performance of the activation protocol, for relevant classes of two-mode Gaussian states.

Citation

Mišta, L., McNulty, D., & Adesso, G. (2014). No-activation theorem for Gaussian nonclassical correlations by Gaussian operations. Physical Review A, 90(2), https://doi.org/10.1103/PhysRevA.90.022328

• Journal Article Type: Article
• Acceptance Date: Jun 25, 2014
• Publication Date: Aug 25, 2014
• Deposit Date: Oct 11, 2017
• Publicly Available Date: Oct 11, 2017
• Journal: Physical Review A
• Print ISSN: 2469-9926
• Electronic ISSN: 2469-9934
• Publisher: American Physical Society
• Peer Reviewed: Peer Reviewed
• Volume: 90
• Issue: 2
• DOI: https://doi.org/10.1103/PhysRevA.90.022328
• Public URL: https://nottingham-repository.worktribe.com/output/733873
• Publisher URL: https://journals.aps.org/pra/abstract/10.1103/PhysRevA.90.022328
• Additional Information: ©2014 American Physical Society