用于量子中继器的极化激元贝尔节点
Polariton Bell Node for Quantum Repeaters
- Moscow Center for Advanced Studies（莫斯科高级研究中心）
- Westlake University（西湖大学）
- St. Petersburg State University（圣彼得堡国立大学）
- Russian Quantum Center（俄罗斯量子中心）
机构由 AI 辅助整理，请以论文原文为准。
AI总结：
该研究提出基于强耦合平面半导体微腔的贝尔测量节点，利用极化激元条件偏振旋转实现受控-Z门与四贝尔态区分，并分析带宽误差及纠缠交换所需链路质量，为量子中继器提供新方案。
AI中文摘要：
我们提出了一种基于平面半导体微腔的贝尔测量节点，该微腔工作在强耦合区，用于量子中继器。腔光子与量子阱激子杂化形成极化激元，其兼具光子和物质准粒子的特性。加载到一个极化激元模式中的控制光子会改变随后入射的目标光子所经历的偏振响应。这种条件旋转由自旋依赖的激子-激子相互作用触发的自感应拉莫尔进动与横电和横磁腔模分裂引起的偏振拍频之间的相互作用所决定。我们确定了实验条件，使得在理想极限下能够实现受控-Z门并区分所有四个贝尔态。单侧散射方案在相同假设下提供了比标量克尔参考更低的作用阈值。在选定的工作点，窄带极限下带宽引起的识别误差随脉冲带宽的四次方缩放。额外的固定输入旋转进一步降低了该误差。我们描述了远程存储器之间的纠缠交换，并确定了获得纠缠输出所需的基本链路的最低质量。
英文摘要：
We propose a Bell-measurement node for quantum repeaters based on a planar semiconductor microcavity operating in the strong-coupling regime. Cavity photons hybridize with quantum-well excitons to form polaritons combining properties of photons and matter quasiparticles. A control photon loaded into one polariton mode changes the polarization response seen by a subsequently incident target photon. This conditional rotation is governed by the interplay of self-induced Larmor precession triggered by spin-dependent exciton-exciton interactions and the polarization beats caused by the splitting of transverse-electric and transverse-magnetic cavity modes. We identify conditions of the experiment that enable implementation of a controlled-Z gate and allow to distinguish all four Bell states in the ideal limit. The one-sided scattering scheme provides a lower interaction threshold than a scalar Kerr reference under the same assumptions. At a selected operating point, the bandwidth-induced identification error scales as the fourth power of the pulse bandwidth in the narrow-band limit. An additional fixed input rotation reduces this error even further. We describe the entanglement swapping between remote memories and determine the minimum quality of the elementary links needed to obtain an entangled output.
