三光子纠缠W态隐形传输令牌总线网的保真度计算

Token-bus Network Fidelity of Quantum Teleportation by Three-photon Entangled W State

计算了三光子W态隐形传输令牌总线网的保真度.通过计算发现在整个量子网络通信过程中,对于给定的分析角θ,保真度仅与系数|a|2有关;随着分析角θ的增加,保真度出现最大值所对应的系数|a|2相应减小,取θ=π/4、π/2、3π/4时可使保真度达最大值1,此时对应的|a|2分别为0.724、0.5和0.276.对于给定的系数|a|,保真度仅与分析角θ有关;若|a|=0,则无论θ为何值,保真度始终为0;若|a|=|b|=0.7071,则当θ=π/2、3π/2时保真度达最大值1.

The fidelity of three-photon W state teleportation token bus network is calculated.The calculation indicates that,for a given analysis angle θ,the fidelity are related only with the coefficient｜a｜^2s during the processes of quantum network communication.With the increase of analysis angles,the maximum fidelity of the corresponding coefficient｜a｜2s correspondingly reduced.When θ=π/4,π/2,3π/4,the fidelity are up to the maximum 1,and the corresponding｜a｜2s are 0.724,0.5,and 0.276,respectively.For a given coefficient｜a｜,the fidelity are related only with the analysis angles θ.If｜a｜=0,the fidelity is always 0 regardless of the value of θ.When｜a｜=｜b｜=0.7071 and θ=π/2,3π/2,the fidelity are up to the maximum 1.