Detta är en digital seminarieserie i kondenserade materiens fysik och atomfysik, med syfte att koppla samman forskare från olika nordiska universitet. Samtalen är informella och ska inspirera till diskussioner och interaktioner.
Jan Arlt (Aarhus University)
The physics of strongly interacting quantum systems is a challenging many-body problem that remains to be understood in its full complexity. I will discuss the case of impurities with strong attractive or repulsive interactions in a quantum degenerate gas of 39K atoms. By using a Ramsey-type sequence, we observe quasiparticle states: the attractive and repulsive polarons. The interferometric signal allows us to extract polaron energies for a wide range of interaction strengths, complementing earlier spectroscopic measurements. Furthermore, several dynamical regimes towards the formation of the Bose polaron are identified. These results improve the understanding of quantum impurities interacting strongly with a bosonic environment and demonstrate how many-body states can be probed using Ramsey interferometry.
Zoom-länk: https://nordita.org/zoom/nvcms