Optical tweezers with light aligned along the particle’s trajectory enable playing tennis with light rackets
2025-09-24
Optical tweezers can rapidly manipulate dielectric objects for applications ranging from microcentrifuges to controlling droplets and particles in a “lab-in-air” configuration. Here, we uniquely combine light propagation that is predominantly parallel to the particle’s orbital track—rather than primarily perpendicular as in conventional vortices—with operation in air. We measure a 7-micrometer sphere circulating at 20,400 rounds per minute [340 hertz (Hz)] along 120-micrometer circumference tracks, achieving accelerations up to 10 times that of gravity (98 square meters per second). Our trap’s optical orbital angular momentum of ℓ = 242ℏ per photon, combined with the gaseous environment, enables high circulation frequencies and underdamped operation at a high mechanical quality factor, Q . Together, our Q - f product of 5300 Hz facilitates low dissipation in combination with rapid particle manipulation. This advancement could substantially expand the impact of dynamic optical traps, particularly in fundamental measurements.