Optical tweezers throw and catch single atoms

Abstract

Single atoms movable from one place to another would enable a flying quantum memory that can be useful for dynamic quantum computing architectures. Guided atoms, e.g., by optical tweezers, provide a partial solution, but the benefit of flying qubits could be lost if they still interact with the guiding means. Here we propose and experimentally demonstrate freely flying atoms that are not guided but instead thrown and caught by optical tweezers. We provide a set of proof-of-principle flying atom demonstrations, which include atom transport through optical tweezers, atom arrangements by flying atoms, and atom scattering off optical tweezers. In experiments, cold rubidium atoms at 40 µK temperature are thrown by accelerating optical tweezers, freely fly with up to a speed of 0.65 m/s and free-flying distance of 4.2 µm, and are recaptured and stopped by decelerating optical tweezers at a transportation efficiency of 94(3)%. Flying atoms suggest possible applications such as defect correction in a tweezer trap atom array, fast atom-array formation, Rydberg-atom collision studies, and dynamic quantum computing architectures.