Deterministic Delivery of a Single Atom

Using optical dipole forces we have realized a conveyor belt for single atoms. This device can transport a single or any desired small number of neutral atoms over a distance of a centimeter with sub-micrometer precision. A standing wave dipole trap is loaded with a prescribed number of cesium atoms from a magneto-optical trap. Mutual detuning of the counter-propagating laser beams moves the interference pattern, allowing us to accelerate and stop the atoms at preselected points along the standing wave with a transportation efficiency close to 100 %. The trapping field can also be accelerated to eject a single atom into free flight with well-defined velocities.