Zhang Kai, Wang Wei, Liu Shengshuai, Pan Xiaozhou, Du Jinjian, Lou Yanbo, Yu Sheng, Lv Shuchao, Treps Nicolas, Fabre Claude, Jing Jietai
State Key Laboratory of Precision Spectroscopy, Joint Institute of Advanced Science and Technology, School of Physics and Electronic Science, East China Normal University, Shanghai 200062, China.
Laboratoire Kastler Brossel, Sorbonne Université, CNRS, ENS-PSL Research University, Collège de France, 4 place Jussieu, 75252 Paris, France.
Phys Rev Lett. 2020 Mar 6;124(9):090501. doi: 10.1103/PhysRevLett.124.090501.
Multipartite entanglement serves as a vital resource for quantum information processing. Generally, its generation requires complex beam splitting processes which limit scalability. A promising trend is to integrate multiple nonlinear processes into a single device via frequency or time multiplexing. The generated states in these schemes are useful for quantum computation. However, they are confined in one or two beams and hard to be spatially separated for applications in quantum communication. Here, we experimentally demonstrate a scheme to generate spatially separated hexapartite entangled states by means of spatially multiplexing seven concurrent four-wave mixing processes. In addition, we show that the entanglement structure characterized by subsystem entanglement distribution can be modified by appropriately shaping the pump characteristics. Such reconfigurability of the entanglement structure gives the possibility to target a desired multipartite entangled state for a specific quantum communication protocol. Our results here provide a new platform for generating large scale spatially separated reconfigurable multipartite entangled beams.
多体纠缠是量子信息处理的重要资源。一般来说,其生成需要复杂的分束过程,这限制了可扩展性。一个有前景的趋势是通过频率或时间复用将多个非线性过程集成到单个器件中。这些方案中生成的态可用于量子计算。然而,它们局限于一束或两束光中,并且难以在空间上分离以用于量子通信。在此,我们通过空间复用七个并发的四波混频过程,实验演示了一种生成空间分离的六体纠缠态的方案。此外,我们表明,通过适当地塑造泵浦特性,可以修改以子系统纠缠分布为特征的纠缠结构。这种纠缠结构的可重构性使得针对特定量子通信协议生成所需的多体纠缠态成为可能。我们的结果为生成大规模空间分离的可重构多体纠缠光束提供了一个新平台。