Spin correlations between individual colliding atomic pair

We experimentally study spin-2 dynamics between two colliding individual~85Rb~atoms,~trapped in tight optical tweezers.~The two colliding 85Rb atoms have effective attractive interactions that are not favorable for collision experiments using ultra-cold gases. Observing the individual pairs also allow for direct investigation of correlation between the magnetic sub-states of the two atoms, who keeps perfect correlation throughout our second long experiment times. Contrary to both finite temperature many-body experiments and zero-temperature two-body experiments, our finite temperature two-body experiments show relaxation dynamics rather than coherent spin-waves. Our experiments indicate that spin-exchange collisions may also provide a useful entanglement mechanism at finite temperatures, which will be less prone to heating during an experiment.