Engineering Application of Optical Tweezers

Abstract

Optical Tweezers is a technology to trap for transparent particles and creatures such as viruses and bacteria. These samples are trapped by the optical radiation pressure force generated by irradiating a focused laser beam. This technology can trap a spherical particle in water solution with the diameter from ?m to nm. A metal particle can be trapped at the center of two laser beams arranged at regular intervals. A non-spherical sample can be prevented from rotating by trapping its edge with multiple lasers. Although atoms can’t be trapped by optical tweezers, they can be trapped using laser cooling and magneto-optical trap. The viscosity of this water solution is obtained by measuring the force trapping the particle and viscosity measurement in the micro-region can be achieved by optical tweezers.