Parameters controlling of vortex solitons in nonlocal nonlinear medium with gradually characteristic length

Abstract

This paper discusses the dynamics of vortex beam in nematic liquid crystals with the tunable characteristic length (CL) of response function. It is found that the transition of the soliton states with different widths during propagations can be controlled by changing the CL under the condition that the nonlocal degree is constant. Furthermore, the transitions propagation of different soliton state is stable and can resist noise. In addition, the numerical results prove that the parameters of vortex solitons, such as rotating periods of angles, orbital angular momentum (OAM), gradient force upon micro-particles all can be controlled conveniently at the desired positions. The controllable density of OAM and gradient force have important academic value and application prospect in the field of optical tweezers and spanner.