Modeling Particle Trapping Using Focused Radiation of an Optical Fiber Mode

The numerical simulation results for optical trapping of silicon nanoparticles using lensed single-mode fibers at a wavelength of 1550 nm are presented. A single lensed fiber is shown to provide stable trapping of particles with a radius of up to 100 nm, whereas for larger particle sizes trapping becomes unstable due to increasing scattering force. An optical tweezers design based on two opposing lensed fibers is proposed, which makes it possible to expand significantly the size range of trapped particles. The sensitivity of the trapping force to fiber misalignment is analyzed. The obtained results can be used in the design of compact fiber optical tweezers for manipulating dielectric nanostructures and micro-objects in microfluidic systems.