Quantum many-body information

量子多体信息

• 批准号: RGPIN-2014-06630
• 负责人: Poulin, David
• 金额: $ 3.28万
• 依托单位: Université de Sherbrooke
• 依托单位国家: 加拿大
• 项目类别: Discovery Grants Program - Individual
• 财政年份: 2017
• 资助国家: 加拿大
• 起止时间: 2017-01-01 至 2018-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=633051
• 关键词: Quantum; many; body; information

Microscopic particles, such as electrons, atoms, and certain microfabricated devices, do not behave as common sense would dictate. Instead, they obey the strange laws of quantum mechanics. These mathematical laws predict for instance that a microscopic particle can be at two places at the same time. While it is hard, if not impossible, to get an intuitive sense about these laws, they are mathematically well understood, they have lead to many scientific predictions, and they have never been contradicted by an experiment. It is by studying the laws of quantum mechanics that devices such as the laser and the transistor were theoretically discovered, before being fabricated. These two devices led to the information revolution, which has impacted all spheres of human activity.While quantum mechanics is at the heart of the information age, the information itself remains classical: the bits processed by a smartphone do not take two different values at a given time, or any such quantum weirdness. Quantum information science is preparing the next information revolution, where quantum mechanical effects are harnessed to enhanced our information processing ability. Quantum communication systems enable unconditionally secure private communication (in contrast to current cryptographic schemes that can be broken with sufficient computing power). Quantum information processors offer an exponential speed-up for certain computations such as factoring integers (with applications in code breaking) and the simulation of quantum mechanical systems (with applications in physics, chemistry, and biology). And these few examples are only the tip of the iceberg.But quantum systems are extremely vulnerable to errors of all kinds, which poses major roadblock to the development of these technologies. If left unattended, these errors will quickly corrupt the quantum information. Scientists have devised fault-tolerant quantum computation, a set of methods to cope with these errors, which is the central theme of my research. While this remedy is well founded theoretically, it entails an explosion of resources required to quantum compute. For instance, with existing schemes, it takes several millions of noisy quantum bits to do the job of a single clean quantum bit. This overhead represents a serious obstacle to the realization of certain quantum technologies, and the main objective of this research proposal is to find theoretical methods to significantly reduce that overhead. Obviously, improving the quality of the physical devices is one way to suppress the overhead. However, it is by improving the software, i.e. the fault-tolerant techniques themselves, that the most significant improvement can be obtained.In the next five years, my NSERC supported research will combine ideas and techniques from theoretical computer science and many-body physics in innovative ways to reduce this overhead. This will be achieve by 1) Enhancing the ways in which fault-tolerant techniques are currently being decoded; 2) Devising new ways to manipulate information fault-tolerantly; and 3) Discovering new phases of matter that naturally protect quantum information. Much like the field itself, my approach is multidisciplinary. I have acquired a unique expertise in these research areas and have assembled an interdisciplinary team of talented young researchers. With this team, I will continue to propose new innovative fault-tolerant methods that will take quantum information processing from a theoretical dream to reality. Canada is already at the forefront of quantum information, and my program will contribute to increase our knowledge in this field and create opportunities for students to learn and apply this knowledge.

显微镜颗粒，例如电子，原子和某些微生物设备，并不像常识所规定那样行为。相反，他们遵守量子力学的奇怪定律。这些数学定律预测，例如，微观粒子可以同时在两个地方。虽然很难（即使不是不可能）对这些定律有直觉的感觉，但它们在数学上是充分理解的，但它们导致了许多科学的预测，并且从未与实验相矛盾。正是通过研究量子力学定律，在制造之前，在理论上发现了激光和晶体管等设备。这两种设备导致了信息革命，这影响了人类活动的所有领域。虽然量子力学是信息时代的核心，但信息本身仍然是经典的：智能手机处理的位在给定时间或任何此类量子怪异度都不会占据两个不同的值。量子信息科学正在准备下一个信息革命，其中利用量子机械效应以增强我们的信息处理能力。量子通信系统可以无条件安全的私人通信（与当前可以通过足够的计算能力破坏的密码方案相比）。量子信息处理器为某些计算提供了指数加速，例如保理整数（用于破坏代码中的应用）和量子机械系统的仿真（以及物理，化学和生物学中的应用）。这几个例子只是冰山一角。但是量子系统极易受到各种错误的影响，这为这些技术的开发带来了主要的障碍。如果无人看管，这些错误将迅速破坏量子信息。科学家已经设计了容忍故障的量子计算，这是解决这些错误的一组方法，这是我研究的中心主题。尽管从理论上讲，这种补救措施是良好的基础，但它需要大量计算所需的资源。例如，使用现有方案，完成单个清洁量子位的工作需要数百万个嘈杂的量子位。该开销代表了实现某些量子技术的严重障碍，该研究建议的主要目的是找到理论方法以显着减少开销。显然，提高物理设备的质量是抑制开销的一种方法。但是，正是通过改进软件，即耐故障技术本身，可以获得最重大的改进。在接下来的五年中，我的NSERC支持的研究将结合理论计算机科学和多体物理学的想法和技术，以创新的方式减少这一头顶。这将通过1）增强目前正在解码的耐故障技术的方式来实现； 2）设计新的方法来操纵信息故障； 3）发现自然保护量子信息的物质的新阶段。就像该领域本身一样，我的方法是多学科的。我在这些研究领域获得了独特的专业知识，并组建了一个由才华横溢的年轻研究人员组成的跨学科团队。有了这个团队，我将继续提出新的具有创新性故障的方法，这些方法将从理论上的梦想到现实进行量子信息处理。加拿大已经处于量子信息的最前沿，我的计划将有助于提高我们在这一领域的知识，并为学生提供学习和应用这些知识的机会。