The optical tweezers are used to trap the particles embedded in a suitable fluid. The optical trap efficiency is significantly enhanced for nonlinear particles which response to the Kerr effect. The optical transverse gradient force makes these particles’ mass density in trapping region increasing, and the Kerr medium can be created. When the laser Gaussian beam propagates through it, the self-focusing, and consequently self-trapping can appear. In this paper, a model describing the laser self-trapping in nonlinear particle solution of optical tweezers is proposed. The expressions for the Kerr effect, effective refractive index of nonlinear particle solution and the intensity distribution of reshaped Gaussian laser beam are derived, and the self-trapping of laser beam is numerically investigated. Finally, the guide properties of nonlinear particles-filled trapping region and guiding condition are analysed and discussed.

光镊用于捕获嵌入在合适流体中的颗粒。对于响应克尔效应的非线性粒子，光阱效率显着提高。光学横向梯度力使这些粒子在俘获区的质量密度增加，可以产生克尔介质。当激光高斯光束通过它时，会出现自聚焦，从而出现自陷。本文提出了一种描述光镊非线性粒子解中激光自陷的模型。推导了克尔效应、非线性粒子解的有效折射率和整形高斯激光束强度分布的表达式，并数值研究了激光束的自陷。最后，