High-dimensional quantum key distribution (QKD) provides ultimate secure communication with secure key rates that cannot be obtained by QKD protocols with binary encoding. However, so far the proposed protocols required additional experimental resources, thus raising the cost of practical high-dimensional systems and limiting their use. Here, we analyze and demonstrate a novel scheme for fiber-based arbitrary-dimensional QKD, based on the most popular commercial hardware for binary time bins encoding. Quantum state transmission is tested over 40 km channel length of standard single-mode fiber, exhibiting a two-fold enhancement of the secret key rate in comparison to the binary Coherent One Way (COW) protocol, without introducing any hardware modifications. This work holds a great potential to enhance the performance of already installed QKD systems by software update alone.
翻译:高维量子密钥分布(QKD)为最终的安全通信提供了安全的关键速度,而QKD协议不能以二元编码获得。然而,到目前为止,拟议的协议需要额外的实验资源,从而提高实用高维系统的成本并限制其使用。在这里,我们分析和演示了一个基于二元时间文档编码最受欢迎的商业硬件的基于纤维的任意立体 QKD新方案。量子州传输经过40公里长的标准单体纤维频道测试,与二元共振一线协议相比,秘密密钥速度增加了2倍,而没有引入任何硬件修改。这项工作极有可能仅通过软件更新而提高已经安装的QKD系统的性能。