Engineering a Noiseless and Broadband Raman Quantum Memory for Temporal Mode Manipulation

单模宽带量子存储器提供了独特的能力，可以增强和扩展未来量子网络的性能。一方面，它们促进了在高时钟频率下时间多路复用产生纯单光子，这可以显著地提高光子产生速率。另一方面，它们的单模特性允许作为宽带分束器操作，该分束器可以在用于信息编码的新基础上操作。它们在量子体系结构中的有效性取决于保存和恢复输入量子态的非经典特性的能力，因此需要低噪声操作。本文详细介绍了我们通过一种新方法在降低先前建立的拉曼存储器协议中的噪声方面的最新进展。通过实施这种噪声抑制方案，我们能够证明在存储单光子态之后恢复非经典状态的可行性，这在标准的拉曼存储器中是不可能的。该项目属于EPSRC量子组件主题。

Single-mode broadband quantum memories provide unique capabilities that can enhance and expand the performance of future quantum networks. On the one hand, they facilitate the temporally multiplexed production of pure single photons at high clock rates, which can dramatically increase photon generation rates. On the other hand, their single mode nature allows for operation as a broadband beam splitter that can operate on novel bases for information encoding. Their usefulness within quantum architectures hinges on the ability to both preserve and to retrieve the non-classicality of the input quantum state, thus requiring low-noise operation.This report details our recent progress in reducing the noise in the previously established Raman memory protocol via a novel method. By implementing this noise suppression scheme we are able to demonstrate the feasibility of retrieving a non-classical state following the storage of a single photon state, a thus-far impossibility in the standard Raman memory.This project falls under the EPSRC Quantum components theme.