Speaker: Antonio Rubio
Affiliation: MPQ
Date: Tuesday, 16 March 2021 at 12:00
Location: Online seminar
Ultracold atoms loaded in optical lattices have enabled studies in many exciting directions. On the one hand, these systems are almost ideal realizations of Hubbard models, while on the other hand, they make it possible to efficiently prepare arrays of closely spaced atoms, which can be used to tailor exotic interatomic interactions, e.g. by exciting them to Rydberg states. The opportunities for this platform have been further extended by quantum-gas microscopy, which allows the detection of site-resolved observables by using a high-resolution objective. In this talk, I will present two recent results from our bosonic quantum-gas microscope in MPQ.
In the first part of the talk, I will discuss experiments on the periodically driven Bose-Hubbard model. While driven many-body systems are generically expected to heat up, at high drive frequencies these heating timescales can be extremely long, a phenomenon known as Floquet prethermalization. In our experiment, we monitor the drive-induced heating by measuring the emergence of site-resolved defects, and find evidence of an exponential-in-frequency suppression of the heating rates.
The second part will focus on our recent observation of cooperative subradiance in a subwavelength array of atoms. By probing the system with a weak laser drive we are able to measure its spectral response and observe of two exciting properties: 1) a narrowing of the linewidth set by the quantum limit of the individual atoms, 2) a high reflectivity from the system, even though it is composed of only a single atomic layer.