THERMAL ENTANGLEMENT IN SPIN SYSTEMS

Chunfang Sun, Taotao Hu, Gangcheng Wang +2 more

Some new Hamiltonians are constructed via the unitary Yang-Baxter matrices [Formula: see text] acting on a Hamiltonian H0 which describes nearest spin-spin interaction. By the concept of concurrence, we explore the thermal entanglement of these systems. We find that the interaction of z-component of two neighboring spins g has great influences on the thermal entanglement. It not only influences the critical temperature Tc, but can also influence the critical magnetic field Bc.

Guo‐Feng Zhang, Shu‐Shen Li, Liang Jiu-Qing

Jeffrey Scott Pratt

N. Canosa, R. Rossignoli

We examine the entanglement of thermal states of n spins interacting through an XYZ type Heisenberg coupling in the presence of a uniform magnetic field, by evaluating the negativities of bipartite partitions of the whole system and subsystems. The corresponding limit temperatures for entanglement are also examined. Results indicate that limit temperatures for global entanglement depend on the type of partition and are higher than those limiting pairwise entanglement, and that their behavior with anisotropy and applied magnetic field may differ significantly from that of the corresponding mean field critical temperature.

Bruno Nachtergaele, Robert Sims, Günter Stolz

We prove an upper bound proportional to the surface area for the bipartite\n entanglement of the ground state and thermal states of harmonic oscillator systems with\n disorder, as measured by the logarithmic negativity. Our assumptions are satisfied for some\n standard models that are almost surely gapless in the thermodynamic limit.

Jianping Li