Realizing itinerant Rydberg models through distance-selective dissipation

• Applicant: Dr. Pascal Weckesser
• Subject Area: Optics, Quantum Optics and Physics of Atoms, Molecules and Plasmas
• Term: Funded in 2023
• Project identifier: Deutsche Forschungsgemeinschaft (DFG) - Project number 516378631

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.

• DFG Programme: WBP Fellowship
• International Connection: USA
• Host: Professor Waseem S. Bakr