Theoretical investigation of the optical trapping force and torque on cylindrical micro-objects

We investigate theoretically the experimentally observed nature of the optical trapping force present on elongated, cylindrically shaped micro-objects. The objects chosen have either flat or spherical ends and elongated cylindrical bodies of various length-to-radii ratios. The trapping force, if present, occurs when the objects are placed in the focal region of a highly divergent laser beam. Results indicate that cylindrical objects can be trapped aligned with the laser beam axis.