Extreme quantum nonlinear optics with strongly coupled atoms and photons

近年来，已经有令人印象深刻的光-物质相互作用和基本量子逻辑操作的演示。这些耦合的光-物质系统构成了优秀的量子信息存储设备的基础，将发射器的自旋状态变量(固定量子比特)映射到光场(飞行量子比特)。我们建议将纳米光学电路与单原子集成(目标1)，并操纵强耦合偶极极化子(目标2)，以实现量子网络和自下而上的量子模拟器。该计划的目的是利用单个光子与具有奇异拓扑的光子带隙材料原子之间的强相互作用，以及超冷里德堡原子之间的长程偶极耦合，从而获得在经典领域中迄今不存在的能力。*总的来说，我们的愿景是将各种纳米光子结构与冷原子相结合，并利用里德堡原子之间的强原子间相互作用。先进的纳米制造能力为目标1的拟议活动提供了技术基础，而超冷里德堡原子的新陷阱组态形成了目标2的研究活动的基础。另外，线性电路的全部“量子”功能是通过原子物质量子比特实现的，信息编码为(A)单个原子的内部超精细自旋态和(B)原子系综的集体态。与光学光子相配合，量子位类型(A)将作为基本的量子逻辑单元，而量子位类型(B)将提供量子存储。原子和光子激发之间的相互转换将通过单个原子到光子晶体的强辐射耦合和通过与原子系综的集体增强发射来完成，该方案的预期成果包括：*(1)在集成光网络上实现单个中性原子由光子连接在一起的功能量子电路。*(2)利用光子晶体波导的真空涨落来模拟原子-原子(光子-光子)相互作用来模拟量子磁性的新范例。*(3)利用超冷里德堡晶格气体进行量子储存库工程。*(4)利用里德堡实现光学量子门和功能量子存储器极化激元。这些实验将由本科生进行，研究生和博士后研究人员。这个应用程序要求为他们的工资、设备、旅行和与出版物相关的费用提供资金。加拿大将直接受益于培训这些人以及实现量子信息科学的新技术和科学前沿。**

In recent years, there have been impressive demonstrations of light-matter interactions and elementary quantum logic operations. These coupled light-matter systems form the basis for excellent quantum information storage devices, mapping spin state variable ("stationary qubit") of an emitter to and from optical fields ("flying qubit"). We propose to integrate nanoscopic optical circuits with single atoms (Objective 1) and to manipulate strongly coupled dipolar polaritons (Objective 2) for the realizations of quantum networks and bottom-up quantum simulators. The approach of the proposed program is to utilize the strong interactions between single photons and atoms with exotic topologies set by photonic bandgap materials and the long-range dipolar coupling between ultracold Rydberg atoms, leading to the capabilities that have not existed heretofore in the classical realm.***Overall, our vision is to integrate diverse nanophotonic structures with cold atoms and to utilize the strong inter-atomic interactions between Rydberg atoms. Advanced nanofabrication capability provides the technical foundation of the proposed activities for Objective 1, while new trapping configuration for ultracold Rydberg atoms form the basis for the research activities for Objective 2. The full "quantum" functionality for otherwise linear circuits is achieved by atomic matter qubits, with the information encoded into (a) internal hyperfine spin states of single atoms and (b) collective states of atomic ensembles. In concert with optical photons, qubit type (a) will serve as elementary quantum logic units, while qubit type (b) will provide quantum memory. The inter-conversion between atomic and photonic excitation will be accomplished by the strong radiative coupling of single atoms into photonic crystals and by the collective enhanced emission with atomic ensembles, with the quantum wiring between stationary qubits enabled by transporting quantum states of single photons.***The anticipated outcomes of the proposal include the following:***(1) The realization of functional quantum circuits with single neutral atoms wired together by photons over integrated optical networks.***(2) A new paradigm for emulating quantum magnetism with atom-atom (photon-photon) interactions tailored by vacuum fluctuations of photonic crystal waveguides.***(3) Quantum-reservoir engineering with ultracold Rydberg lattice gases.***(4) The implementation of optical quantum gates and functional quantum memories with Rydberg polaritons.***These experiments will be carried out by undergraduate, graduate, and post-doctoral researchers. This application requests funding for their salary, equipment, travel, and costs associated with publications. Canada will directly benefit by training these individuals and by enabling new technological and scientific frontiers of quantum information science.**