基于卫星的纠分布在1200公里
Juan Yin1,2, Yuan Cao1,2, Yu-Huai Li1,2
1Department of Modern Physics and Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei 230026, China.
概括
基于卫星的量子网络实现了超过1203公里的长距离纠分布,克服了以前的距离限制. 这一突破使得基础量子物理测试和可扩展的量子网络成为可能.
科学领域:
- 量子物理学
- 量子通信网络
背景情况:
- 长距离纠分布对于量子物理测试和量子网络至关重要.
- 以前的距离限制 (~100公里) 主要是由于通道损失.
研究的目的:
- 通过卫星显示杂光子对在前所未有的距离上的分布.
- 克服基于地面光纤的纠分布的局限性.
主要方法:
- 使用卫星平台来分发纠的光子对.
- 使用两个不同长度 (1600-2400公里) 的卫星至地面下线链路.
- 确保严格的爱因斯坦局部条件进行测量.
主要成果:
- 在两处地面位置之间成功分布了1203公里的纠光子对.
- 证实了两个光子纠的生存.
- 观察到贝尔不等式的违反 (2.37 ± 0.09),证实了量子相关性.
- 与直接光纤传输相比,实现了显著更高的有效链路效率.
结论:
- 基于卫星的分布是一种可行的远距离量子纠方法.
- 这项技术克服了以前的距离限制,为全球量子网络铺平了道路.
- 这些结果支持量子力学的基础测试.
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