在噪声情况下远程制备四比特团簇态

Remote preparation of four-qubit cluster states in noisy environment

本文采用团簇态作为量子信道,讨论了4种噪声对远程制备四比特团簇态的影响.首先分析在理想情况下,制备者Alice利用团簇态作为量子信道,通过构造巧妙的测量基,帮助接收者Bob获取所需制备的目标四比特团簇态;然后讨论在4种噪声影响下远程制备四比特团簇态,且利用保真度来描述输出态与输入态之间的接近程度.发现不同类型的噪声对远程量子态制备的影响程度不同.尤其相位噪声,在远程量子制备四比特团簇态的过程中,系统的保真度不受待制备量子态的相位因素的影响,然而其他3种噪声都受待制备量子态的相位因素的影响.

With a cluster state as the quantum channel, we present a scheme for remote preparation of four-qubit cluster states in noisy environment. In this scheme, we firstly consider the protocol for remotely preparing any four-qubit cluster state under ideal circumstances. In the following, we put forward the scheme for remote preparation of four-qubit cluster states under the influence of four kinds of noisy channels, i.e. the bit-flip noise、the phase-damping noise、the amplitudedamping noise and the depolarizing noise. Finally, we use the fidelity to describe the distance between the output state and the desired prepared state. Without loss of generality, different types of noise have various effects on the process of the quantum remote state preparation. For the phase damping noise, the fidelity of the whole system is not affected by the phase factor for the remote state preparation, but the other three kinds of quantum noise are influenced by the phase factors.