A Quantum-Eraser Approach to Heralding High-Quality Single Photons

该计划的目标是设计单模、波长通用、紧凑、可扩展和室温可操作的高速单光子源，用于现代量子光学应用。将利用量子擦除器的概念开发一种无损管理单光子时空状态的全新方法，并详细研究其在各种光学系统中的应用，包括光纤和晶体波导。该方法将在基于光纤的系统中实施，以演示高纯度、电信频带、单光子源，其生产率可能比同等纯度的最先进的单光子源高几个数量级。其智力上的优点是使用由量子频率转换设备制成的量子擦除器，一步完成了三个关键任务，预示着纯单光子的到来：(a)消除光子对之间固有的量子相关性，(b)无损地将预示的单光子裁剪成最佳的时空模式，以用于各种应用，以及(c)通过自然匹配使用更高效的频率上转换检测来提高单光子的产生效率。更广泛的影响是：1)它将开发一种使能技术，用于过渡到实践许多基于单光子的应用，否则这些应用将留在研究实验室，特别是那些利用现有低损耗光纤电信基础设施的应用；2)为学生和博士后提供跨学科的研究活动，他们的培训将跨越量子光学的基础科学与经典光学工程领域之间的桥梁，从而为他们在全球光子学市场上提供竞争优势。

The objective of this program is to devise high-speed single-photon sources that are single mode, wavelength versatile, compact, scalable, and room-temperature operable for use in modern quantum-optics applications. A fundamentally new approach for losslessly managing the spatio-temporal states of single photons will be developed using the concept of quantum erasers and its applications in various optical systems, including fibers and crystalline waveguides, will be studied in detail. The approach will be implemented in a fiber-based system to demonstrate a high purity, telecommunications band, single-photon source whose production rate is potentially orders of magnitude higher than the state-of-the-art single-photon sources of comparable purity.The intellectual merit is to use quantum erasers made from quantum-frequency-conversion devices to accomplish three crucial tasks for heralding pure single photons in a single step: (a) eliminating inherent quantum correlation between the photon pairs, (b) losslessly tailoring the heralded single photons into the optimal spatio-temporal modes for use in various applications, and (c) boosting the single-photon production efficiency by the naturally-matched use of higher-efficiency frequency-up-conversion detection. The broader impacts are: 1) it will develop an enabling technology for transitioning to practice many single-photon-based applications that otherwise will remain in a research laboratory, particularly those that harness the existing low-loss fiber telecommunications infrastructure; 2) it will be a cross-disciplinary research activity for the students and postdocs, whose training will span a bridge between the fundamental science of quantum optics and the classical arena of optical engineering, thereby providing them a competitive advantage in the global photonics marketplace.