量子纠缠是实现量子通信和量子计算的重要资源,其中多体纠缠更是构建量子网络实现全局量子计算的基础。本文主要研究如何利用经典的光子回声技术实现光量子态的三体纠缠。在自由空间中向掺杂稀土离子的固态离子系综中射入经典光场,当离子体系达到相位重构条件时即可获得三束存在纠缠的量子光场。基于本方案纠缠产生的技术特点,发现其在提高量子中继器的工作效率上有着潜在的应用价值。

Quantum entanglement is the key resource to realize quantum communication and quantum computation, among which,the multi-body entanglement is a fundamental resource to construct the quantum networks and perform universal quantum computation.Here, we present a scheme to generate three-body entanglement of light using photon echo technics.By injecting a classical electromagnet field into a crystal doped with rare earth ions placed in free space, three-body entanglement of light pulse could be created when the atomic system dephased.Based on the characteristics of the scheme, we have found that it has a potential application in the improving of the efficiency of quantum repeater.