Nano-Particle Manipulated with Near-Field Optical Tweezers
By applying the direct calculation of Maxwell stress tensor using three-dimensional finite difference time domain method, the feasibility of using a metal-coated fiber probe to create near-field optical tweezers is investigated. Numerical results indicate that these schemes are able to trap nano-particles with lower laser intensity than that required by conventional optical tweezers. The near-field optical trapping systems that are more flexible than conventional optical tweezers are built. In experiments, 120-nm polystyrene particles are trapped in a multi-circular shape with a minimum size of 400 nm. The realization of trapping particles in the range of tens of nanometers largely promotes the role of near-field optical manipulation at the nanometer scale.
Jianzhong Wang and Jingang Qi
J. Tang et al., "Nano-Particle Manipulated with Near-Field Optical Tweezers", Advanced Materials Research, Vols. 299-300, pp. 1068-1071, 2011