We numerically simulate the trapping properties of Rayleigh particles by using focused canonical vortex beam and noncanonical vortex beam. The effects of topological charge and phase distribution of optical vortex on trapping Rayleigh particles are discussed. The results show that when an optical vortex takes different values of topological charge, the focused canonical vortex beam has similar trapping properties of Rayleigh particles: the low refractive index particles can be trapped in two dimensions at the focal point, and the high refractive index particles can be fully stably trapped at a ring of the focal plane. However, when focused noncanonical vortex beam is used to trap Rayleigh particles, for different values of topological charge, the low refractive index particles can be trapped in two dimensions or three dimensions in the focal plane, and the high refractive index particles can be fully stably trapped at several points of the focal plane. Therefore, when focused vortex beam is used to trap Rayleigh particles, the trapping regions and the trapping stability of Rayleigh particles can be adjusted by changing the topologically charge and phase distribution of optical vortex.
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