Conditions for entanglement in spin systems and for multipartite entanglement

Jiang Zhou, Hong Mei Guo

The time evolution of genuine multipartite entanglement is numerically studied in a model many-spin system decohered by a structured spin bath. It is found that multipartite entanglement can be more persistent than the bipartite entanglement and can even evolve into a specific constant under certain conditions. Besides, multipartite entanglement sudden death and sudden birth are observed. It is shown that the randomness of the coupling strength and connectivity between the spins in the environment will suppress these birth and death phenomena. Furthermore, the initial state of the central system plays a significant role in determining multipartite entanglement dynamics.

Rosario Fazio, Chiara Macchiavello

Jeffrey Scott Pratt

Marcus Huber, Nicolai Friis, A. Gabriel +2 more

We analyze multipartite entanglement in systems of spin-½ particles from a relativistic perspective. General conditions which have to be met for any classification of multipartite entanglement to be Lorentz invariant are derived, which contributes to a physical understanding of entanglement classification. We show that quantum information in a relativistic setting requires the partition of the Hilbert space into particles to be taken seriously. Furthermore, we study exemplary cases and show how the spin and momentum entanglement transforms relativistically in a multipartite setting.

Massimo Blasone A, Fabio Dell’Anno, Silvio De Siena +2 more

We investigate the behaviour of multipartite entanglement in finite-size quantum spin systems, resorting to a hierarchy of geometric measures of multipartite entanglement recently introduced in the literature. In particular, we investigate the ground-state entanglement in the XY model defined on finite chains of N sites with periodic boundary conditions. We analyse the behaviour of the geometric measures of (N 1)-partite and (N/2)-partite entanglement and compare them with the Wei‐Goldbart geometric measure of global entanglement.

J. D. M. Vianna, Marco A. S. Trindade, M.C.B. Fernandes