The experiment and theoretical analysis of the completely inelastic collision of microspheres and optical microrotor

Optical tweezers have been successfully utilized in various scientific and engineering fields such as medicine, biology and MEMS. However, there is still a lack of a sophisticated model for optical tweezers on driving complex objects. In this paper a new electromagnetic model of optical tweezers based on moment method is presented. Optical force acting on a single microsphere and two microspheres is experimentally analyzed and the experimental results are compared with the simulated ones which are obtained by our model. A microrotor which can be used as a mixer in a lab-on-chip is also analyzed by the model. The results indicate that the algorithm presented here can be easily extended to multi complex structures and to torque computation algorithms, thus providing a highly flexible and universally useable computation engine.