Acta Sinica Quantum Optica
Thermal Entanglement in a Three-qubit Heisenberg XX Model with Dzyaloshinski-Moriya Interaction
Feng Gao
Abstract
Thermal pairwise entanglement of a three-qubit Heisenberg XX chain with the Dzyaloshinski-Moriya(DM) anisotropic antisymmetric interaction under an external magnetic field and quantum teleportation when using the Heisenberg chain as a channel are investigated.The entanglement and fidelity depending on the DM interaction,magnetic field and temperature are given in detail.The results show that the thermal entanglement can be controlled by magnetic field and DM interaction.Quantum teleportation will be better realized via an ferromagnetic spinchain when the DM interaction and external magnetic field are turned off and the temperature is low.The thermal entanglement cannot completely reflect the teleportation fidelity,and the same thermal entanglement could yield different average teleportation fidelities.