A novel source of quantum light: harnessing cascaded downconversion as a resource for quantum technologies

一种新颖的量子光源：利用级联下转换作为量子技术的资源

• 批准号: RGPIN-2022-03962
• 负责人: Hamel, Deny
• 金额: $ 1.75万
• 依托单位: Université de Moncton
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2022
• 资助国家: 加拿大
• 起止时间: 2022-01-01 至 2023-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=763454
• 关键词: novel; source; quantum; light; harnessing

The first quantum revolution, spurred by the discovery of quantum physics, helped us understand how the world works and led to the development of computer chips and lasers. We are currently on the verge of a second quantum revolution, which will come from technologies designed from the ground up to directly exploit quantum phenomena. Such technologies are expected to transform computing, through quantum processors providing, for certain tasks, exponential speedups relative to today's computers. They will also revolutionize metrology and sensing, with sensors breaking through the sensitivity limits of current technologies, and cryptography, with quantum protocols able to provide absolutely secure communications. A critical requirement for several quantum technologies is the availability of practical methods to produce light possessing quantum properties. Light has the advantage of being able to hold and transfer quantum data effectively, making quantum light sources a key technology for optical quantum computers. Light is also the sole truly feasible method of transferring quantum data quickly over long distances; quantum light sources are therefore an essential requirement for quantum communication and for the development of the quantum internet. Over the last few years, my group has explored how a novel method of producing quantum light, cascaded downconversion, can be used as an enabling resource for various quantum information applications and as a tool to explore fundamental quantum physics. Our efforts have been extremely fruitful, leading to many significant discoveries. While these results conclusively demonstrate the relevance of cascaded downconversion for both fundamental and technological applications, certain roadblocks remain, preventing its widespread adoption for practical use. Most importantly, the method currently suffers from low efficiencies, as even the most efficient nonlinear crystals only convert one out of every million photons. This has limited cascaded downconversion to production rates insufficient for most real-world scenarios. With this new Discovery Grant, I propose a research program aimed at harnessing the potential of cascaded downconversion for quantum information processing. This will be done both through technical developments aimed at addressing the current challenges associated with the process, and by demonstrating its usefulness in implementing a variety of optical quantum information protocols and applications. This research program will be of significant benefit to Canadians. First, through the generation of knowledge and novel technologies of immediate relevance in the burgeoning Canadian quantum sector. Second, by training students and other highly qualified personnel to provide them with the skills required to be active participants in this new Canadian quantum industry which is currently in dire need of skilled workers.

第一次量子革命是由量子物理学的发现引发的，它帮助我们理解了世界是如何运作的，并导致了计算机芯片和激光的发展。我们目前正处于第二次量子革命的边缘，它将来自于直接利用量子现象的技术设计。这些技术有望通过量子处理器改变计算，为某些任务提供相对于当今计算机的指数级速度。它们还将彻底改变计量和传感，传感器突破当前技术的灵敏度限制，以及密码学，量子协议能够提供绝对安全的通信。几种量子技术的关键要求是产生具有量子特性的光的实用方法的可用性。光的优势在于能够有效地保存和传输量子数据，这使得量子光源成为光学量子计算机的关键技术。光也是唯一真正可行的远距离快速传输量子数据的方法；因此，量子光源是量子通信和量子互联网发展的基本要求。在过去的几年里，我的小组已经探索了一种产生量子光的新方法，级联下转换，可以用作各种量子信息应用的使能资源，并作为探索基础量子物理的工具。我们的努力卓有成效，有了许多重大发现。虽然这些结果最终证明了级联下转换与基础和技术应用的相关性，但某些障碍仍然存在，阻碍了其在实际应用中的广泛采用。最重要的是，这种方法目前的效率很低，因为即使是最有效的非线性晶体也只能转换一百万个光子中的一个。这限制了级联向下转换到生产速率，这对于大多数现实场景来说是不够的。有了这个新的发现基金，我提出了一个研究项目，旨在利用级联下转换的潜力进行量子信息处理。这将通过旨在解决当前与该过程相关的挑战的技术发展来实现，并通过展示其在实现各种光量子信息协议和应用中的有用性来实现。这个研究项目将对加拿大人有重大的好处。首先，通过在蓬勃发展的加拿大量子领域产生直接相关的知识和新技术。其次，通过培训学生和其他高素质人才，为他们提供积极参与这个目前急需技术工人的加拿大新量子产业所需的技能。