The realization of quantum networks and quantum computers relies on the scalable generation of entanglement, for which spin-photon interfaces are strong candidates. Current proposals to produce entangled-photon states with such platforms place stringent requirements on the physical properties of the photon emitters, limiting the range and performance of suitable physical systems. We propose a scalable protocol, which significantly reduces the constraints on the emitter. We use only a single optical transition and an asymmetric polarizing interferometer. This device converts the entanglement from the experimentally robust time basis via a path degree of freedom into a polarization basis, where quantum logic operations can be performed. The fundamental unit of the proposed protocol is realized experimentally in this work, using a nitrogen-vacancy center in diamond. This classically assisted protocol greatly widens the set of physical systems suited for scalable entangled-photon generation and enables performance enhancement of existing platforms.

量子网络和量子计算机的实现依赖于纠缠的可扩展生成，自旋光子界面是其强大的候选对象。当前使用这种平台产生纠缠光子状态的提议对光子发射器的物理特性提出了严格的要求，从而限制了合适的物理系统的范围和性能。我们提出了一种可扩展的协议，该协议可显着减少对发射器的约束。我们仅使用一个光学跃迁和一个非对称偏振干涉仪。该器件将纠缠从实验鲁棒性的时间基准通过路径自由度转换为极化基准，可以在其中执行量子逻辑运算。这项协议的基本单元在这项工作中是通过实验实现的，使用金刚石中的氮空位中心。这种经典辅助协议极大地扩展了适用于可伸缩纠缠光子生成的物理系统集，并能够增强现有平台的性能。