Characterization and control of multipartite quantum systems for information processing

基于量子力学定律的信息处理有望在计算和通信方面取得革命性的进步。量子算法执行某些任务的速度远远快于当今最快的计算机，而隐形传态和量子密码学等新型协议可以改变我们目前的通信和信息处理能力。小规模量子信息处理已被证明是可行的，但要实现大规模量子信息处理，挑战在于如何有效地控制多体耦合系统。这些耦合系统在量子区表现出很强的非经典关联或纠缠，在经典区表现出非线性混沌行为。 在这个研究项目中，我的目标是描述和分析多体系统中的量子相互作用，设计和评估有效的量子控制技术，并开发新的量子信息处理协议。这项工作建立在我在量子信息和量子混沌方面正在进行的成功研究计划的基础上，并将重点放在两个领域。首先，我们将分析现实量子系统的控制，并探索混沌如何影响信息处理和宝贵的量子资源(如纠缠)的行为。我们打算研究混沌存在下的噪声和纠错，以及对QIP的反馈控制的使用，这仍然是相对未被探索的。其次，我们将对多体量子关联进行详细的描述，并利用这些关联来开发高效、大规模的QIP协议。我们的基于三方纠缠的最优通信方案将被推广到多方网络。这项研究将涉及分析和数值技术，并将分析现实的物理系统，以便开发一个可以有效实施的量子控制框架。 这项令人兴奋的研究将为有关量子-经典联系的长期争论的问题带来新的见解，并有助于开发一个强大的控制工具箱，用于构建强大的量子技术。该计划将培养高素质的人才，并提高加拿大在QIP研究方面的世界级声誉。

Information processing based on the laws of quantum mechanics offers the promise of revolutionary advances in computing and communication. Quantum algorithms can perform certain tasks dramatically faster than today's fastest computers, and novel protocols such as teleportation and quantum cryptography can transform our current communication and information processing capabilities. Small-scale quantum information processing (QIP) has been demonstrated, but the challenge is to efficiently control multipartite coupled systems for large-scale QIP. These coupled systems can exhibit powerful non-classical correlations or 'entanglement' in the quantum regime, and nonlinear chaotic behaviour in the classical regime. In this research program, my goals are to characterize and analyze quantum interactions in multipartite systems, design and evaluate efficient quantum control techniques, and develop new quantum information processing protocols. This work builds on my ongoing successful research program in quantum information and quantum chaos and will focus on two areas. First, we will analyze the control of realistic quantum systems and explore how chaos affects information processing and the behaviour of valuable quantum resources such as entanglement. We intend to study noise and error correction in the presence of chaos, and the use of feedback control for QIP, which is still relatively unexplored. Second, we will perform detailed characterizations of multipartite quantum correlations and develop efficient, large-scale QIP protocols by exploiting these correlations. Our optimal communication schemes based on tripartite entanglement will be generalized to multiparty networks. The research will involve analytical and numerical techniques, and will analyze realistic physical systems in order to develop a framework of quantum control that can be usefully implemented. This exciting research will lead to new insight into long-debated questions about the quantum-classical connection as well as help to develop a powerful control toolbox for building robust quantum technologies. The program will train highly qualified personnel and enhance Canada's world-class reputation in QIP research.