AI 中文总结
该研究采用极化光纤相位调制器（PFPM）实现全光纤集成平台的高维量子态测量，简化了接收器架构，其四维QKD的每脉冲有限密钥率超现有演示，为高效检测提供了适用平台。
AI 中文摘要
量子态的高效检测是先进的设备无关量子信息协议的基础，这类协议为量子随机数生成、量子密钥分发（QKD）等任务提供了最高级别的安全性。高维编码是提升这类协议性能的自然途径，可增强噪声鲁棒性并提高信息容量，但其实际实现仍具挑战性。高维度下的一个关键实验瓶颈是通常需要用于基选择的有源调制器，这会产生显著的光学损耗并导致偏振敏感操作。极化光纤相位调制器（PFPM）是一种光纤本征的电光技术，可自然应对这些挑战，兼具低于1dB的插入损耗、本征偏振独立性，且与标准电信光纤直接兼容。本文报道了PFPM在全光纤集成平台中用于有源量子态测量的首次应用。我们的四维量子位接收器中的基选择通过单个PFPM实现，大幅简化了接收器架构。作为基准，我们开展了四维QKD会话，获得的每脉冲有限密钥率据我们所知超过了所有先前报道的QKD演示。我们的结果确立了极化光纤电光调制作为光纤集成量子信息处理中高效检测的广泛适用平台。
英文摘要
Efficient detection of quantum states underpins advanced device-independent quantum-information protocols that provide the ultimate level of security for tasks including quantum random number generation and quantum key distribution (QKD). High-dimensional encoding is a natural route to boost the performance of such protocols, offering enhanced noise resilience and higher information capacity, yet their practical implementation remains challenging. A key experimental bottleneck in higher dimensions is the typical need of active modulators for basis selection, which incur substantial optical losses and polarization-sensitive operation. Poled optical fiber phase modulators (PFPMs) are a fiber-native electro-optic technology that naturally addresses these challenges, combining sub-dB insertion loss, intrinsic polarization independence, and direct compatibility with standard telecommunications fiber. Here we report the first use of a PFPM for active quantum-state measurements in a fully fiber-integrated platform. Basis selection in our receiver for four-dimensional qudits is achieved using a single PFPM, substantially simplifying the receiver architecture. As a benchmark, we perform a four-dimensional QKD session and obtain a finite secret-key rate per pulse that, to the best of our knowledge, surpasses all previously reported QKD demonstrations. Our results establish poled-fiber electro-optic modulation as a broadly applicable platform for high-efficiency detection in fiber-integrated quantum information processing.
Comments9 pages, 5 figures. Please see the parallel paper "An optical-fibre-integrated buffer for packet-switched quantum networks'' that was submitted today to the arXiv
