Journal of Southwest University
Influence of Decoherence of Two-Qubit Ising Model on Entanglement and Fidelity
Zhenghong He
Abstract
An investigation of the entanglement and fidelity for two-qubit Ising model in an external uniform magnetic field showed that the entanglement degree oscillated with increasing phase decoherence in the initial stage and decreased with the increase in phase decoherence thereafter,the decline of the entanglement degree being greater with greater phase decoherence.When the initial state of the system was on its eigenstate,the concurrence was zero,or it did not change with the evolution of phase decoherence.The fidelity of the system exhibied an obvious periodic change and tended to remain at a constant value with the increase in phase decoherence.The entanglement degree and fidelity of the two-qubit Ising model could be enhanced or weakened through controlling magnetic field B.