Hefei National Laboratory for Physical Sciences at Microscale and Department of Modern Physics, University of Science and Technology of China, Hefei, Anhui, PR China.
Sci Rep. 2012;2:626. doi: 10.1038/srep00626. Epub 2012 Sep 4.
Faithful transmission of quantum information is a crucial ingredient in quantum communication networks. To overcome the unavoidable decoherence in a noisy channel, to date, many efforts have been made to transmit one state by consuming large numbers of time-synchronized ancilla states. However, such huge demands of quantum resources are hard to meet with current technology and this restricts practical applications. Here we experimentally demonstrate quantum error detection, an economical approach to reliably protecting a qubit against bit-flip errors. Arbitrary unknown polarization states of single photons and entangled photons are converted into time bins deterministically via a modified Franson interferometer. Noise arising in both 10 m and 0.8 km fiber, which induces associated errors on the reference frame of time bins, is filtered when photons are detected. The demonstrated resource efficiency and state independence make this protocol a promising candidate for implementing a real-world quantum communication network.
量子信息的保真传输是量子通信网络的关键组成部分。为了克服嘈杂信道中不可避免的退相干，迄今为止，人们已经做出了许多努力，通过消耗大量时间同步辅助状态来传输一个状态。然而，这种对量子资源的巨大需求很难满足当前的技术，这限制了实际应用。在这里，我们通过实验演示了量子错误检测，这是一种经济的方法，可以可靠地保护量子位免受位翻转错误的影响。通过修改后的 Franson 干涉仪，任意未知的单光子和纠缠光子的偏振态可以确定性地转换成时间-bin。当光子被探测到时，在 10 m 和 0.8 km 光纤中产生的噪声会过滤掉时间-bin 参考帧上的相关误差。所展示的资源效率和状态独立性使该协议成为实现实际量子通信网络的有前途的候选方案。
