Multi-copy activation of genuine multipartite entanglement in continuous-variable systems

Abstract

Multi-copy activation of genuine multipartite entanglement (GME) is a phenomenon whereby multiple copies of biseparable but fully inseparable states can exhibit GME. This was shown to be generically possible in finite dimensions. Here, we extend this analysis to infinite dimensions. We provide examples of GME-activatable non-Gaussian states. For Gaussian states, we apply a necessary biseparability criterion for the covariance matrix and show that it cannot detect GME activation. We further identify fully inseparable Gaussian states that satisfy the criterion but show that multiple and, in some cases, even single copies are GME. Thus, we show that the covariance-matrix biseparability criterion is not sufficient even for Gaussian states.

8+11 pages, 2 figures; extended results, version accepted for publication

References in corpus (6)

• Entanglement detection
• Entanglement Certification $-$ From Theory to Experiment
• Taming multiparticle entanglement
• Purification of genuine multipartite entanglement
• Multipartite continuous-variable entanglement
• Quantum gates and multipartite entanglement resonances realized by non-uniform cavity motion

Cited by in corpus (4)

• Detecting genuine multipartite entanglement in multi-qubit devices with restricted measurements
• Protocols for sharing genuine multipartite entanglement by employing copies of biseparable states
• Experimental verification of multi-copy activation of genuine multipartite entanglement
• Revisiting Gaussian genuine entanglement witnesses with modern software