利用二粒子部分纠缠态实现开靶目标的非局域量子可控非(CNOT)门的受控操作

Controlled implementation of a nonlocal and open-target destination quantum controlled-Not (CNOT) gate using partially entangled pairs

提出利用二粒子部分纠缠态概率性地实现开靶目标的非局域量子可控非(CNOT)门的操控方案.首先考虑利用3个二粒子部分纠缠态实现3个靶目标共享的非局域量子CNOT门的受控操作,然后将该方案推广到N个靶目标共享的情形.在该方案中,控制端Alice的局域正定算符值测量(POVM)起着关键作用,给出了该测量算符的数学表式.值得注意的是,用二粒子部分纠缠态可确定性地实现非局域CNOT门.

We show how a nonlocal and open-target destination quantum controlled-Not（CNOT）gate can be probabilistically implemented by using partially entangled pairs of particles.We first investigate the controlled implementation of a nonlocal and three-target destination CNOT gate using three partially entangled pairs,and then generalize the scheme to the case of N-target destination.In this scheme,Alice s local generalized measurement described by a positive operator valued measurement （POVM） plays a key role. We construct the required POVM. It is worth noting that deterministic and exact implementation of a nonlocal CNOT gate can be realized using partially entangled pairs.