Speakers
Description
Studies of interactions between a single ion and a neutral atom, in a well-defined quantum state, constitute a corner stone in quantum chemistry. Yet, the number of techniques which enable measurement of cold collision processes and cross-section measurement is handful. We present three different fronts to improve the measurements resolution, applicability and accuracy in the measurements of such interactions between laser-cooled atoms and ions trapped in RF Paul traps.
First, by controlling the velocity atoms in trapped in optical lattices with high resolution, we investigated the energy dependence of several processes within the 0.1-10 millikelvin range. Second, we developed a quantum logic technique that enables the measurement of collision and reaction cross-sections between ultra-cold atoms and any ion species with the help of an ancillary logic-ion. We further used this technique to measure the cross-seciton of spin-exchange and charge-exchange processes between atom-ion pairs that are otherwise inaccessible in our system. Finally, we present a new calibration technique that enables an in-situ estimation of the Langevin rate coefficient to high certainty. Preliminary results of the measured cross-sections possibly hint for quantum effects associated with the ultracold regime.
