Polaron formation in Rydberg systems and Rydberg excitations as a probe of correlated quantum matter

近年来，原子量子气体中的里德堡激发已成为探索介观量子杂质问题的新前沿。里德堡激发不仅被低能激发所掩盖，而且还被分子束缚态所掩盖，这使得它们与传统的极化子不同。到目前为止，研究仅限于描述浸没在玻色子系统中的里德堡杂质。在这个项目中，我们将开发新的理论工具，使我们能够描述费米子和相互作用环境中的里德堡激发。为此，我们结合了泛函行列式和变分波函数方法来研究费米子激发对杂质的修饰。基于这些结果，我们将探索里德堡激发作为多体环境中的关联的探测。为此，我们研究了吸收光谱中低聚物线相对强度与配对和高阶关联函数的关系。此外，我们还研究了里德堡杂质如何作为Feshbach分子形成的原位探针，并利用干涉技术探索多体系统的实时动力学。

In recent years, Rydberg excitations in atomic quantum gases have become a new frontier to explore mesoscopic quantum impurity problems. Rydberg excitations are dressed not only by low-energy excitations but by molecular bound state which makes them distinct from conventional polarons. So far studies have been restricted to the description of Rydberg impurities immersed in bosonic systems. In this project we will develop novel theoretical tools that allow us to describe Rydberg excitations in fermionic and interacting environment. To this end we combine functional determinant and variational wave function approaches to study the dressing of the impurity by fermionic excitations. Based on these results we will explore Rydberg excitations as a probe of correlations in a many-body environment. To this end we study the relation of the relative the oligmer line strengths in the absorption spectrum to pair and higher-order correlation functions. Moreover, we investigate how Rydberg impurities can be used as an in-situ probe of Feshbach molecule formation and to explore the real-time dynamics of many-body systems using interferometric techniques.