QuIC-TAQS: Implementation of a Neutral-Atom-Photonic-Cluster State

量子信息科学与技术（QIST）有望通过开发新的计算、通信和传感模式，从根本上改变我们的技术格局，正如国家量子倡议所确定的那样。QIST对国家需求的潜在长期影响是多方面的，包括促进科学进步以及经济和国家安全。量子互连（QuICs）是实现量子标准技术（QIST）所需的一类重要组件，它能够在不同的物理系统之间传输量子信息。该团队将开发并演示中性原子和光子（或光“粒子”）之间的新界面。我们的方法是基于产生一个原子和光子的相关系统，称为集群状态，可用于量子计算，传感和通信。通过利用集成光学（片上）平台来操纵电信波长的光子，PI和他的合作者的目标是开发一个可以很容易地部署在量子网络应用中的系统。这将对基础科学和工程产生重大影响。例如，我们的工作为创建和控制大型量子系统提供了新的方法，这可以为模拟自然提供新的方法。该项目通过培训研究生和本科生以及一系列外展活动，为多样化的量子就绪劳动力做出了贡献。为了产生中性原子-光子团簇态，本项目将光单原子发射的原始光子团簇态的确定性生成与集成光学平台相结合。全光操作将在芯片上实现，将原始簇态组合（“融合”）成更大的簇态，可以用于量子信息处理，并能够克服量子网络中的损耗。具体来说，原始光子团簇态是由单个中性铷原子的光子发射产生的，这些原子被激光捕获并强耦合到由氮化硅制成的普通纳米光子晶体波导中定义的分离光学腔中。激光和微波控制使原子发射确定的单光子波包序列，沿着波导轴传播。光子在其发射时间内携带有关原子状态的信息。光子可以占据这些“时间仓”的叠加态，对应于一个时间仓量子比特（“量子位”）。光子被耦合到一个外部集成光学芯片中，该芯片包含快速开关，用于将光子包与为光子“融合门”操作设计的适当延迟相结合，该操作通过检测芯片输出的光子子集来实现。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Quantum information science and technology (QIST) holds promise to transform radically our technological landscape by developing new computational, communications and sensing modalities as identified in the National Quantum Initiative. The potential long-term impacts on national needs of QIST are diverse and include enhancing scientific progress as well as economic and national security. Quantum Interconnects (QuICs), which enable transferring quantum information between different physical systems, are an essential class of components needed for the realization of QIST. The team will develop and demonstrate a novel interface between neutral atoms and photons, or light ‘particles’. Our approach is based on generating a correlated system of atoms and photons, known as a cluster state, that can be used for quantum computation, sensing and communications. By utilizing an integrated-optics (on-chip) platform to manipulate photons at telecommunications wavelengths, the PI and his collaborators aim to develop a system that can be readily deployed in quantum network applications. The impacts on basic science and engineering will be significant. For example, our work enables new ways to create and control large quantum systems, which could provide new approaches to simulate nature. This project contributes to a diverse quantum-ready workforce through training of graduate and undergraduate students and range of outreach activities.To produce neutral-atom-photonic cluster states this project combines the deterministic generation of primitive photonic cluster states via light single-atom emission with an integrated-optics platform. All-optical operations will be implemented on-chip to combine (‘fuse’) the primitive cluster states into larger ones that can serve for quantum information processing and enable overcoming loss in a quantum network. Specifically,the primitive photonic cluster states are generated by photon emission from single neutral rubidium atoms that are laser-trapped and strongly coupled to separate optical cavities defined in a common nanophotonic-crystal waveguide fabricated in silicon nitride. Laser and microwave controls cause the atom(s) to emit deterministically a sequence of single-photon wave packets that propagate along the waveguide axis. The photons carry information about the atomic state in their emission time. Photons can occupy a superposition of these ‘time bins’, corresponding to a time-bin quantum bit (‘qubit’). The photons are coupled into an external integrated-optics chip containing fast switches for combining the photon packets with appropriate delays designed for photonic ‘fusion gate’ operations, which are implemented by detecting a subset of photon outputs from the chip.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.