Thermal entanglement of spins in mean-field clusters
نویسندگان
چکیده
We determine thermal entanglement in mean field clusters of N spin one-half particles interacting via the anisotropic Heisenberg interaction, with and without external magnetic field. For the xxx cluster in the absence of magnetic field we prove that only the N = 2 ferromagnetic cluster shows entanglement. An external magnetic field B can only entangle xxx anti-ferromagnetic clusters in certain regions of the B−T plane. On the other hand, the xxz clusters of size N > 2 are entangled only when the interaction is ferromagnetic. Detailed dependence of the entanglement on various parameters is investigated in each case. PACS Numbers: 03.65.Ud, 05.50.+9, 75.10.Jm. email:[email protected] Corresponding author, email:[email protected]
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