Entanglement Teleportation via One Two-Qubit Spin Evolution Quantum Channel

Abstract

Entanglement teleportation via treating one two-qubit evolution Ising model as the quantum channel with Dzyaloshinskii-Moriya (DM) interaction under inhomogeneous magnetic field is investigated in detail. We mainly concentrate on the effects about the purity (r) of the initial state about the channel system, the DM interaction (D) and the inhomogeneous magnetic field (b) on the entanglement of the output state and the average fidelity. We show that varying the parameters D and b can influence on the frequency of the oscillation to the teleported entanglement and the average fidelity, and the amplitude of the oscillation can be enhanced evidently by changing r or tuning the entanglement of the input state. The teleported entanglement can fall to zero and maintain to be zero for a short period of time before entanglement recovers when we change the three parameters, one interesting point is that the time interval of the teleported entanglement sudden death will be shorter when we choose the higher purity r of the initial channel state. It also shown us that choosing the smaller values of D and b can broaden the length of the average fidelity where the region is superior to 2/3 and raising the purity of initial state of the quantum channel can expand the height of the average fidelity where the region is superior to 2/3.