CAS Key Laboratory of Quantum Information, University of Science and Technology of China, Hefei, 230026, China.
Synergetic Innovation Center of Quantum Information and Quantum Physics, University of Science and Technology of China, Hefei, 230026, P.R. China.
Nat Commun. 2018 Aug 24;9(1):3407. doi: 10.1038/s41467-018-05669-5.
The faithful storage and coherent manipulation of quantum states with matter-systems would enable the realization of large-scale quantum networks based on quantum repeaters. To achieve useful communication rates, highly multimode quantum memories are required to construct a multiplexed quantum repeater. Here, we present a demonstration of on-demand storage of orbital-angular-momentum states with weak coherent pulses at the single-photon-level in a rare-earth-ion-doped crystal. Through the combination of this spatial degree-of-freedom (DOF) with temporal and spectral degrees of freedom, we create a multiple-DOF memory with high multimode capacity. This device can serve as a quantum mode converter with high fidelity, which is a fundamental requirement for the construction of a multiplexed quantum repeater. This device further enables essentially arbitrary spectral and temporal manipulations of spatial-qutrit-encoded photonic pulses in real time. Therefore, the developed quantum memory can serve as a building block for scalable photonic quantum information processing architectures.
利用物质系统对量子态进行忠实存储和相干操纵，将能够实现基于量子中继器的大规模量子网络。为了实现有用的通信速率，需要高度多模量子存储器来构建多路复用量子中继器。在这里，我们展示了在掺稀土离子晶体中利用弱相干脉冲在单光子水平上对轨道角动量态进行按需存储的实验结果。通过将该空间自由度（DOF）与时间和光谱自由度相结合，我们创建了一个具有高多模容量的多 DOF 存储器。该器件可以作为具有高保真度的量子模式转换器，这是构建多路复用量子中继器的基本要求。该器件还能够实时对空间量子比特编码的光子脉冲进行实质上任意的光谱和时间操纵。因此，所开发的量子存储器可以作为可扩展的光子量子信息处理架构的构建模块。
