  Spatial adiabatic passage (SAP) is a process that facilitates the transfer of
a wave packet between two localized modes that are not directly coupled, but
rather interact through an intermediate third mode. By employing a
counter-intuitive adiabatic pulse sequence, this technique achieves minimal
population in the intermediate state and high transfer efficiency. Here, we
report the implementation of SAP for transferring massive particles between
three micro-optical traps. We begin by preparing ultracold fermionic atoms in
low vibrational eigenstates of one trap and then manipulate the distance
between the three traps to execute the SAP protocol. We observe a smooth
transfer of atoms between the two outer traps, accompanied by a low population
in the central trap. We validate our findings and underscore the significance
of the counter-intuitive sequence by reversing the order of the pulse sequence.
Additionally, we investigate the influence of the tunneling rate and the time
delay between the motion of the two external tweezers on the fidelity of the
process. Our results open up new possibilities for advanced control and
manipulation schemes in optical tweezer array platforms.
