Experimental Quantum Seminar - Phillip Preiss: (Heidelberg University) “Zooming in on Ultracold Few-Fermion Systems”

“Zooming in on Ultracold Few-Fermion Systems”
Strongly interacting Fermi systems are at the heart of many open questions in condensed matter, nuclear, and high-energy physics. Ultracold atoms provide a unique opportunity to study their most interesting aspects - such as strongly correlated superuids and collective excitations - in a tunable laboratory setting.
I will report on recent experiments that grant complete control over mesoscopic ultracold fermion systems. Using optical tweezers and novel methods for atom-resolved imaging in free space, we are able to manipulate and characterize strongly interacting systems on the single-particle level. With these techniques, we have recently observed the “birth” of a collective mode of a few-fermion system in two-dimensional trap. This system in its ground state exhibits a shell structure of stable magic numbers of particles. In many-body spectroscopy, we find pairwise excitations and identify a well-dened resonance as the few-body precursor of the Higgs amplitude mode.
Our results point to a new direction for ultracold quantum gases, where few-body systems can be used to emulate atomic and nuclear physics with systematically tunable parameters.
Host: Bonnie Fleming