Dr Haroche and Dr Wineland led independent teams which, beginning in the 1980s, devised ways to measure and manipulate particles while preserving superposition.
Actual superposition (as opposed to the cat-in-a-box sort) is easiest with small objects, for which there are fewer pathways along which the superposition can break down.
The pulses served to cool them even further, by settling them into their lowest possible energy states, and then to nudge them into a superposition of two different energy states.