Macroscopic observables detecting genuine multipartite entanglement and partial inseparability in many-body systems
1 Faculty of Physics, University of Vienna - Boltzmanngasse 5, 1090 Vienna, Austria, EU
2 Department of Theoretical Physics and Astrophysics, Masaryk University - Kotářśka 2, 61137 Brno, Czech Republic, EU
Received: 2 July 2012
Accepted: 16 January 2013
We show a general approach for detecting genuine multipartite entanglement and partial inseparability in many-body systems by means of macroscopic observables (such as the energy) only. We show that the obtained criteria detect large areas of genuine multipartite entanglement and partial entanglement in typical mixed many-body states, which are not detected by other criteria. As genuine multipartite entanglement is a necessary property for several quantum information theoretic applications such as, e.g., secret sharing or certain kinds of quantum computation, our methods can be used to select or design appropriate condensed matter systems.
PACS: 03.65.Ud – Entanglement and quantum nonlocality (e.g. EPR paradox, Bell's inequalities, GHZ states, etc.) / 03.67.Mn – Entanglement measures, witnesses, and other characterizations
© EPLA, 2013