Seminarium Optyczne

Ultracold polar molecules are a promising platform for upcoming quantum technologiessuch as quantum computing and quantum simulation. However, applications are limited byloss due to molecule-molecule collisions. Surprisingly, such loss is observed even forchemically stable molecules. This is attributed to "sticky collisions"; The formation ofparticularly long-lived collision complexes that mediate the loss.In this talk, I will discuss our current understanding of these sticky collisions. I willshow conservation of angular momentum in collisions leads to sticking times orders ofmagnitude below previous estimates [1], but that excitation of collision complexes by thetrapping laser is fast and can explain the observed loss. These predictions are validatedquantitatively by two independent experiments [2], but fail to describe others [3]. It hasbeen speculated that in the latter experiments total angular momentum and molecularhyperfine states might not be conserved, extending sticking times by orders of magnitude.I will present a theoretical framework to study the dynamics of sticky collisions, whichshows small static electric fields can lead to non-conservation of angular momentum whilenuclear spin is typically conserved [4].[1] Christianen, Zwierlein, Groenenboom, and Karman, PRL, 123, 123402 (2019)[2] Liu et al. Nature Physics, 16, 1132 (2020)[3] Bause et al. PRR, 3, 033013 (2021)[4] Man, Groenenboom, and Karman arXiv 2203.13598

Seminarium z użyciem połączenia internetowegohttps://zoom.us/j/97696726563(meeting ID: 97696726563, password: 314297)