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International Journal of Quantum Information

ENTANGLEMENT IN THE XY SPIN CHAIN WITH NONUNIFORM EXTERNAL MAGNETIC FIELDS

JUNPENG CAO, Z. Z. Sun, YIN SUN, YUPENG WANG, X. R. Wang

Published Sep 1, 2005• 1 citation
Publisher

Abstract

We study the entanglement in the three-site Heisenberg XY model with nonuniform external magnetic fields and obtain analytic expressions for the measures of entanglement in the system with both the periodic and the open boundary conditions. We show that both the ground state and the excited states of the system possess remarkable entanglement properties and the entanglement clearly depends on the magnitude of external fields. We obtain the pairwise thermal entanglement of the system. We also discuss the boundary effects on the entanglement.

DOI
10.1142/s0219749905001146

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