Speaker
Description
We investigate quantum atom-ion scattering in the s-wave regime using a hybrid system comprising a single ${}^{138}\text{Ba}^{+}$ ion trapped in a linear Paul trap and a near-degenerate ${}^6\text{Li}$ Fermi gas confined in a crossed optical dipole trap. The ion is positioned within the Fermi gas and will undergo collisions. Inelastic collisions are directly related to formation of molecular states. The rates of inelastic collision can be tuned via magnetic Feshbach resonances using external fields, allowing for the enhancement or suppression of molecular formation channels. The existence of those channels depend on electronic states. To date, we have characterised both two-body (atom-ion) and three-body (atom-atom-ion) processes. While Feshbach resonances are well-established in neutral atom experiments, achieving the ultracold regime in RF traps remains challenging due to micromotion, which limits the minimum achievable collision energy.
Building on our previous characterisation of resonances’ position, width, and asymmetry across parameter space (collisional energy, magnetic field, and atomic spin polarization), we present an ongoing study focused on manipulating the substructure of single three-body Feshbach resonances. We demonstrate that this substructure is modulated by the external fields and the ion motion. These investigations aim to refine the theoretical understanding of few-body dynamics in atom-ion systems and establish the precise control necessary for future many-body quantum simulations.
| Academic level | Postdoctoral researcher |
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