Propagation characteristics and optical forces exerted upon a Rayleigh dielectric sphere for a controllable dark-hollow beam

Zhirong Liu, Xun Wang, Kelin Huang

Propagation characteristics and optical forces exerted upon a Rayleigh dielectric sphere for a novel controllable dark-hollow beam (CDHB) are analyzed theoretically and illustrated numerically. In view of the unique focusing characteristics that a sharp, peak-centered, and adjustable configuration would be produced in the focal region, a tightly focused CDHB could be exploited to trap and manipulate particles with high-refractive index in the focal vicinity. Furthermore, it is significant that the CDHB tweezers’ trapping efficiency and optical trap stiffness could be finely controlled by adjusting either the targeted beam’s order or the central dark size controlling parameter. Finally, the trapping stability conditions are analyzed. The results obtained here are of interest and importance in optical manipulations and investigations for a CDHB.

DOI