A New Method Based on Conservation Momentum to Calculate the Trapping Force Using FDTD Algorithm

In this paper, A new method based on the conservation of momentum theory to calculate the trapping force on microsphere are presented. Using 2-D FDTD algorithm, the distribution of electric and magnetic fields in trapping system is simulated, then the momentum density distribution and trapping force can be easily get. Many parameters are taken into accounted involving wavelength of optical source, waist radius, diameter of microsphere and refractive index. The simulation results are in good agreement with the other experimental observation.