Optical trapping and rotation of airborne absorbing particles with a single focused laser beam
Abstract
We measure the periodic circular motion of single absorbing aerosol particles that are optically trapped with a single focused Gaussian beam and rotate around the laser propagation direction. The scattered light from the trapped particle is observed to be directional and change periodically at 0.4–20 kHz. The instantaneous positions of the moving particle within a rotation period are measured by a high-speed imaging technique using a charge coupled device camera and a repetitively pulsed light-emitting diode illumination. The centripetal acceleration of the trapped particle as high as ∼20 times the gravitational acceleration is observed and is attributed to the photophoretic forces.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Mar 10, 2014
- Source ID
- 10.1063/1.4868542
Entities
People
- Jinda Lin
- Yong-qing Li
Organizations
- Army Research Office
- East Carolina University