No-activation theorem for Gaussian nonclassical correlations by Gaussian operations
arXiv:1405.6859 · doi:10.1103/PhysRevA.90.022328
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.
10 pages, 2 figures; to appear in PRA
References in corpus (9)
- Entanglement in continuous variable systems: Recent advances and current perspectives
- No-local-broadcasting theorem for quantum correlations
- Linking Quantum Discord to Entanglement in a Measurement
- All non-classical correlations can be activated into distillable entanglement
- Operational Significance of Discord Consumption: Theory and Experiment
- Measuring bipartite quantum correlations of an unknown state
- Homodyne estimation of Gaussian quantum discord
- Experimental Investigation of the Evolution of Gaussian Quantum Discord in an Open System
- Verification of quantum discord