Scalable and accessible photonics for next-generation quantum networks

基于量子力学的技术可以实现高性能的信息处理、面向未来的安全通信和高灵敏度的计量。由于光子的鲁棒性、多功能性和长相干时间，量子光学为这些实现提供了理想的平台。然而，光子在商业应用中仍然没有被广泛使用，因为它们的检测概率（以及因此它们的检测/处理速率）随着量子状态中光子数量的增长而呈指数下降。因此，虽然固态平台的信息处理能力随着更多数量的量子位（两级系统）而提高，但它在光子学中却会下降，使得实现大多局限于实验室且昂贵。量子光子学的扩展和商业化还需要强大但可扩展的光学系统以及低损耗的量子信息处理。这个发现项目旨在通过利用完善的电信和基于芯片的基础设施来解决这些迫切的需求，同时扩展我在INRS-EMT在集成非线性和量子光学方面开发的非常成功的研究线。具体来说，我的团队已经展示了一种克服缩放问题的方法，通过使用高维（qudit，即量子比特的d级扩展）状态编码，大大增加了存储在少数光子中的信息内容。对于N个光子，这样的量子点具有缩放为d^N的信息容量，因此能够以低光子数实现高处理功率和检测效率。拟议的项目包括两个主要部分，是对这些最近成就的势头的及时资本化：（1）我们将开发高性能和低足迹的复杂光子态源，研究成熟和新引入的材料。将研究在可扩展的、低损耗的、基于光纤的组件（例如干涉仪、调制器）中实现的量子信息处理，以实现复杂但可访问的、基于光子的操作。这些光子产生和操纵模块的开发，针对实际和可商业化的平台，对于在实验室外应用（例如量子安全通信）中部署这些系统至关重要。(2)类似于未来的量子电信网络，光子在其中传播和干涉，将研究光子注入可编程光纤环（即合成晶格结构），以获得对量子态在具有更高成本的商业系统中的行为的新见解。具体研究量子态信息容量如何随着复杂传播而变化，将为未来的网络和量子态设计建立重要的技术诀窍。我们的发现计划将加强我们在集成非线性和非经典光子学方面帮助建立的强大的加拿大存在，走向可商业化和负担得起的量子技术。

Technology based on quantum mechanics can enable high-performance information processing, future-proof secure communications, and highly sensitive metrology. Quantum optics, thanks to photons' robustness, versatility and long coherence times, provides the ideal platform for these realizations. However, photons are still not widely used in commercial applications as their detection probability (and thus their detection/processing rate) decreases exponentially with a growing number of photons in the quantum state. Thus, while information processing power for solid-state platforms improves with a larger number of qubits (two-level systems), it degrades in photonics, making realizations mostly lab-confined and expensive. Extending and commercializing quantum photonics also necessitates robust, yet scalable optical systems, as well as low-loss quantum information processing. This Discovery project aims to address these urgent needs by making use of well-established telecommunications and chip-based infrastructures, while expanding the extremely successful research lines I have developed at INRS-EMT in integrated nonlinear and quantum optics. Specifically, my team has demonstrated a route to overcome scaling issues by greatly increasing the information content stored in only a few photons through using high-dimensional (qudit, i.e. the d-level extension of a qubit) state encoding. For N photons, such qudits have an information capacity that scales as d^N, thus enabling high processing powers and detection efficiencies with a low photon number. The proposed project, comprised of two main parts, is a timely capitalization on the momentum of these recent achievements: (1) We will develop high-performance and low-footprint sources of complex photon states, investigating both well-established and newly-introduced materials. Quantum information processing implemented in scalable, low-loss, fiber-based components (e.g. interferometers, modulators) will be studied to achieve complex, yet accessible, photon-based operations. The development of these photon generation and manipulation blocks, targeted in practical and commercializable platforms, will be critical in enabling the deployment of these systems in out-of-the-lab applications (e.g. quantum secure communications). (2) In analogy to future quantum telecommunications networks, where photons propagate and interfere, the injection of photons into programmable fiber-loops (i.e. synthetic lattice structures) will be studied to gain new insights into how quantum states behave in commercial systems which feature much higher costs. Investigating specifically how e.g. quantum state information capacities change with complex propagation will establish important know-how for future network and quantum state design. Our Discovery program will reinforce the strong Canadian presence we helped establish in integrated nonlinear and non-classical photonics, towards commercializable and affordable quantum technologies.