Guan Jian-Yu, Xu Feihu, Yin Hua-Lei, Li Yuan, Zhang Wei-Jun, Chen Si-Jing, Yang Xiao-Yan, Li Li, You Li-Xing, Chen Teng-Yun, Wang Zhen, Zhang Qiang, Pan Jian-Wei
Department of Modern Physics and National Laboratory for Physical Sciences at Microscale, Shanghai Branch, University of Science and Technology of China, Hefei, Anhui 230026, China.
CAS Center for Excellence and Synergetic Innovation Center in Quantum Information and Quantum Physics, Shanghai Branch, University of Science and Technology of China, Hefei, Anhui 230026, China.
Phys Rev Lett. 2016 Jun 17;116(24):240502. doi: 10.1103/PhysRevLett.116.240502. Epub 2016 Jun 13.
Quantum communication has historically been at the forefront of advancements, from fundamental tests of quantum physics to utilizing the quantum-mechanical properties of physical systems for practical applications. In the field of communication complexity, quantum communication allows the advantage of an exponential reduction in the transmitted information over classical communication to accomplish distributed computational tasks. However, to date, demonstrating this advantage in a practical setting continues to be a central challenge. Here, we report a proof-of-principle experimental demonstration of a quantum fingerprinting protocol that for the first time surpasses the ultimate classical limit to transmitted information. Ultralow noise superconducting single-photon detectors and a stable fiber-based Sagnac interferometer are used to implement a quantum fingerprinting system that is capable of transmitting less information than the classical proven lower bound over 20 km standard telecom fiber for input sizes of up to 2 Gbits. The results pave the way for experimentally exploring the advanced features of quantum communication and open a new window of opportunity for research in communication complexity and testing the foundations of physics.
从量子物理的基础测试到利用物理系统的量子力学特性进行实际应用，量子通信在历史上一直处于进步的前沿。在通信复杂性领域，量子通信相较于经典通信具有指数级减少传输信息的优势，从而能够完成分布式计算任务。然而，迄今为止，在实际环境中证明这一优势仍然是一项核心挑战。在此，我们报告了一种量子指纹识别协议的原理验证实验演示，该协议首次超越了传输信息的经典极限。利用超低噪声超导单光子探测器和基于光纤的稳定萨格纳克干涉仪，实现了一个量子指纹识别系统，对于高达2 Gbit的输入大小，该系统在20公里标准电信光纤上能够传输比经典证明的下限更少的信息。这些结果为通过实验探索量子通信的先进特性铺平了道路，并为通信复杂性研究以及检验物理基础打开了新的机遇之窗。
