论文标题
与M-SPGD算法的单模光纤耦合，用于远程量子通信
Single-mode fiber coupling with a M-SPGD algorithm for long-range quantum communications
论文作者
论文摘要
基于卫星的量子通信是实现全球尺度量子网络的一种有前途的方法。对于自由空间量子通道，单模光纤耦合对于改善日光量子键分布（QKD）的信号噪声比和与标准纤维QKD的兼容性尤为重要。但是，在强大的大气湍流下达到高效且稳定的单模耦合效率仍然具有实验性挑战。在这里，我们基于随机并行梯度下降（M-SPGD）算法的模态版本开发具有自适应光学（AO）系统的单模接收器，并在8 km Urban陆地自由空间通道上测试其性能。在强大的大气湍流下，M-SPGD AO系统在单模纤维耦合效率中获得了约3.7 dB的改善，并且可以显着抑制波动，这可以在自由空间的远程量子通信中找到其应用。
Satellite-based quantum communication is a promising approach for realizing global-scale quantum networks. For free-space quantum channel, single-mode fiber coupling is particularly important for improving signal-to-noise ratio of daylight quantum key distribution (QKD) and compatibility with standard fiber-based QKD. However, achieving a highly efficient and stable single-mode coupling efficiency under strong atmospheric turbulence remains experimentally challenging. Here, we develop a single-mode receiver with an adaptive optics (AO) system based on a modal version of the stochastic parallel gradient descent (M-SPGD) algorithm and test its performance over an 8 km urban terrestrial free-space channel. Under strong atmospheric turbulence, the M-SPGD AO system obtains an improvement of about 3.7 dB in the single-mode fiber coupling efficiency and a significant suppression of fluctuation, which can find its applications in free-space long-range quantum communications.
