Quantum information science over continuous variables

该项目将关注（i）连续变量量子信息科学的理论基础以及（ii）使用量子光学方法的实际实现问题。连续变量系统的量子信息科学为量子比特等有限维系统上的原始量子信息提供了一种有希望的和重要的替代方案。该研究计划的主要课题包括研究通过大距离噪声信道制备和分布纠缠态、将一般量子态映射到高斯态的一般“高斯化协议”、能够高效区分不同光子数的量子中继器和光子探测器。理论部分将关注高斯量子运算的重要集合，区分量子态的最佳协议及其在密码学中的应用，退相干理论以及量子信息科学方法在量子统计系统中的应用。

This project will be concerned with the (i) mathematical-theoretical foundations of quantum information science over continuous variables as well as with (ii) issues of the practical realisation using methods of quantum optics. Quantum information science with continuous-variable systems offers a promising and important alternative to the original quantum information over finite-dimensional systems such as qubits. Key topics of this research proposal include the study of the preparation and distribution of entangled states through noise channels over large distances, general "Gaussifier protocols" that map general quantum states onto Gaussian states, quantum repeaters and photon detectors that can distinguish different photon numbers with high efficiency. The mathematical-theoretical part will be concerned with the important set of Gaussian quantum operations, optimal protocols to distinguish quantum states with applications in cryptography, decoherence theory and with the application of methods from quantum information science to quantum statistical systems.