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。由于光子的健壮性、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，光子仍然没有在商业应用中得到广泛的应用，因为它们的探测概率(因此它们的探测/处理速率)随着量子态中的光子数量的增加而指数下降。因此，虽然固态平台的信息处理能力随着更多的量子比特(两级系统)的增加而提高，但它在光子学中却有所下降，使得实现大多局限于实验室和昂贵。推广和商业化量子光子学还需要强大而可扩展的光学系统，以及低损耗的量子信息处理。这个探索项目旨在通过利用成熟的电信和基于芯片的基础设施来满足这些迫切需求，同时扩大我在INRS-EMT在集成非线性和量子光学方面开发的极其成功的研究线。具体地说，我的团队已经展示了一种克服可伸缩性问题的方法，通过使用高维(Qudit，即量子比特的d能级扩展)状态编码，极大地增加了仅存储在几个光子中的信息量。对于N个光子，这样的量子数具有可扩展到d^N的信息容量，从而以较低的光子数实现高处理能力和探测效率。该项目由两个主要部分组成，是对这些最新成就势头的及时利用：(1)我们将开发高性能和低占用空间的复杂光子态来源，调查现有的和新引入的材料。在可扩展、低损耗、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将被研究以实现复杂但可访问的基于光子的操作。这些以实用和商业化平台为目标的光子产生和操纵模块的开发，对于使这些系统能够在实验室外的应用(例如量子安全通信)中部署至关重要。(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路(即合成晶格结构)，以获得新的见解，以了解量子态在具有更高成本的商业系统中的行为。具体研究例如量子态信息容量如何随复杂传播而变化，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领域帮助建立的强大的加拿大存在，朝着可商业化和负担得起的量子技术发展。

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.