Quantum enhanced multi-parameter estimation

研究人员已经应用Fisher信息来量化估计单个参数的精度，如简单光学系统中的吸收或相位，并报告量子策略可以超越经典极限的实例。最近，该领域已经发展到探索如何超越经典极限进行多参数估计。量子计量学的关键在于确定参数估计的经典精度极限——毕竟，你需要定义一个极限才能超越它。这个博士项目背后的动机将是探索这个经典极限是否总是合适的，以及从感知的角度探索资源的经典极限意味着什么。我们将努力更好地定义与现实成像和传感场景的每个相关的定义经典极限相对应的测量类别，灵感来自根据所需量化资源将不同计算资源分组的复杂性类别。

Researchers have applied Fisher information to quantify the precision in estimating single parameters such as absorption or phase in simple optical systems and to report instances where quantum strategies can perform beyond the classical limit. Recently, the field has grown to explore how to perform multi-parameter estimation beyond the classical limit. Key to this quantum metrology has been identifying the classical precision limit in parameter estimation - after all, you need to define a limit in order to surpass it. The motivation behind this PhD project will be to explore if this classical limit is always appropriate and explore what a classical limit in resources means from a sensing perspective. We will strive to better define the classes of measurement that correspond to each, relevant, defined classical limit for realistic imaging and sensing scenarios, inspired by complexity classes that group together different computational resources according to the quantified resources required.