Optically induced rotation of anisotropic micro-objects fabricated by surface micromachining

Abstract
Optical trapping and directional high-speed rotation by radiation pressure are demonstrated for anisotropic micro-objects fabricated by reactive ion-beam etching. These micro-objects, which have shape dissymmetry (not bilateral symmetry but rotational symmetry) in the horizontal cross section, rotate about the laser beam axis in the designed direction in a liquid medium (e.g., water or alcohol). The rotation speed is almost proportional to the input laser power.