Observation of elastic collisions between lithium atoms and calcium ions

TL;DR

This study reports the observation of elastic collisions between laser-cooled lithium atoms and calcium ions, demonstrating energy-dependent scattering consistent with semi-classical theory, advancing understanding of atom-ion interactions.

Contribution

First experimental observation of elastic collisions between lithium atoms and calcium ions at cryogenic temperatures using optical trapping and tweezer techniques.

Findings

Elastic collision rates measured at 100 mK to 3 K

Collision cross-section matches semi-classical predictions

Optical tweezer technique enables precise atom-ion overlap

Abstract

We observed elastic collisions between laser-cooled fermionic lithium atoms and calcium ions at the energy range from 100 mK to 3 K. Lithium atoms in an optical-dipole trap were transported to the center of the ion trap using an optical tweezer technique, and a spatial overlap of the atoms and ions was realized in order to observe the atom-ion interactions. The elastic scattering rate was determined from the decay of atoms due to elastic collisions with ions. The collision-energy dependence of the elastic scattering cross-section was consistent with semi-classical collision theory.