Zhu Tian-Xiang, Su Ming-Xu, Liu Chao, Liu Yu-Ping, Wang Chao-Fan, Liu Pei-Xi, Han Yong-Jian, Zhou Zong-Quan, Li Chuan-Feng, Guo Guang-Can
CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei 230026, China.
CAS Center for Excellence in Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei 230026, China.
Natl Sci Rev. 2024 May 1;11(11):nwae161. doi: 10.1093/nsr/nwae161. eCollection 2024 Nov.
Photonic integrated quantum memories are essential for the construction of scalable quantum networks. Spin-wave quantum storage, which can support on-demand retrieval with a long lifetime, is indispensable for practical applications, but has never been demonstrated in an integrated solid-state device. Here, we demonstrate spin-wave quantum storage based on a laser-written waveguide fabricated in a Eu:YSiO crystal, using both the atomic frequency comb and noiseless photon-echo protocols. Qubits encoded with single-photon-level inputs are stored and retrieved with a fidelity of [Formula: see text], which is far beyond the maximal fidelity that can be obtained with any classical device. Our results underline the potential of laser-written integrated devices for practical applications in large-scale quantum networks, such as the construction of multiplexed quantum repeaters in an integrated configuration and high-density transportable quantum memories.
光子集成量子存储器对于构建可扩展量子网络至关重要。自旋波量子存储能够支持按需检索且具有长寿命，这对于实际应用不可或缺，但从未在集成固态器件中得到验证。在此，我们展示了基于在铕掺杂钇硅氧晶体（Eu:YSiO）中制备的激光写入波导的自旋波量子存储，使用了原子频率梳协议和无噪声光子回波协议。用单光子级输入编码的量子比特以[公式：见原文]的保真度进行存储和检索，这远远超过了任何经典器件所能达到的最大保真度。我们的结果突显了激光写入集成器件在大规模量子网络实际应用中的潜力，例如以集成配置构建复用量子中继器以及高密度可运输量子存储器。
