Semiconductor quantum dots are promising building blocks for quantum communication applications. Although deterministic, efficient, and coherent emission of entangled photons has been realized, implementing a practical quantum repeater remains outstanding. Here we explore the statistical limits for entanglement swapping with sources of polarization-entangled photons from the commonly used biexciton-exciton cascade. We stress the necessity of tuning the exciton fine structure, and explain why the often observed time evolution of photonic entanglement in quantum dots is not applicable for large quantum networks. We identify the critical, statistically distributed device parameters for entanglement swapping based on two sources. A numerical model for benchmarking the consequences of device fabrication, dynamic tuning techniques, and statistical effects is developed, in order to bring the realization of semiconductor-based quantum networks one step closer to reality.

中文翻译：

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与半导体纠缠光子源纠缠交换的统计限制

半导体量子点是量子通信应用的有前途的构建模块。尽管已经实现了纠缠光子的确定性、高效和相干发射，但实现实用的量子中继器仍然很出色。在这里，我们探讨了纠缠交换与来自常用双激子-激子级联的偏振纠缠光子源的统计限制。我们强调调整激子精细结构的必要性，并解释为什么经常观察到的量子点中光子纠缠的时间演化不适用于大型量子网络。我们基于两个来源确定了用于纠缠交换的关键、统计分布的设备参数。用于对设备制造、动态调谐技术的后果进行基准测试的数值模型，