Realizing itinerant Rydberg models through distance-selective dissipation

量子多体系统的实现和探测是实验量子模拟和量子信息研究的核心。在过去的几十年中，超冷量子气体已经成为模拟开放和封闭量子系统的领跑者之一。对于这些系统，已经投入了大量的努力来引入远程相互作用，因为它们提供了新的和未探索的量子相图。电子激发的里德伯原子提供了一个强大的平台，可以实现强而远的相互作用，最远可达几微米。到目前为止，大多数里德伯实验都是在冷冻气体状态下进行的，由于里德伯态的寿命相对较短，原子的运动与此无关。该方案的一个关键挑战和主要目标是实现“流动”系统。在这样的系统中，光学晶格内相干隧穿和里德伯相互作用的贡献与哈密顿量同样相关。到目前为止，这些模型的实现仍然难以实现，因为各种方法，如里德堡敷料，受到无法控制的快速原子损失的限制。在这项研究中，我设计了一种新型的里德堡诱导相互作用，它允许人们在抑制不必要的原子损失的同时进入流动状态。相互作用是由受控的耗散损耗引起的，通过光激发进入里德堡大二聚体态。在强耗散的极限下，多体系统被映射到扩展的Hubbard模型上，该模型在可调的、距离选择的晶格位置上具有硬核玻色子排斥——这是一种迄今尚未在实验中探索的新的远程模型。在这项工作中，我将把这种相互作用应用于存储在二维光学晶格中的铷原子。利用我们的量子气体显微镜，我将以单点分辨率研究原子水平上的耗散和远程相关性。我将进一步探索大量子多体态的猝灭动力学，并研究远程相关的建立，最终使观察复杂量子相和强相关物质的形成成为可能。

Realizing and probing quantum many-body systems is at the heart of experimental quantum simulation and quantum information. Over the past decades, ultracold quantum gases have emerged as one of the frontrunners in simulating open and closed quantum systems. For these systems, an extensive effort has been devoted in introducing long-range interactions, as they offer novel and unexplored quantum phase diagrams. Electronically excited Rydberg atoms provide a powerful platform for realizing strong and long-range interactions reaching up to few micrometers. So far, most Rydberg experiments operate in the frozen gas regime, where the motion of the atoms is irrelevant due to the comparably short lifetime of the Rydberg state. A key challenge and major aim of this proposal is to realize “itinerant” systems. In such systems, the contributions of coherent tunneling within an optical lattice and Rydberg interactions are equally relevant for the Hamiltonian. So far, the implementation of these models remained elusive as various approaches, such as Rydberg dressing, were limited by uncontrollably fast atom loss. In this study, I engineer a new type of Rydberg-induced interaction, which allows one to enter the itinerant regime while suppressing unwanted atom loss. The interaction is induced by controlled, dissipative losses through optical excitation into Rydberg macrodimer states. In the limit of strong dissipation, the many-body system is mapped onto an extended Hubbard model featuring hard-core bosonic repulsion on tunable, distance-selective lattice sites – a new long-range model that has so far not been explored experimentally. In this work, I will apply this interaction to rubidium atoms stored in a 2D optical lattice. Using our quantum gas microscope, I will investigate the dissipative and long-range correlations on the atomic level with single-site resolution. I will further explore the quench dynamics of larger quantum many-body states and investigate the build-up of long-range correlations, ultimately enabling the observation of complex quantum phases and formation of strongly correlated matter.