We analyze the optical radiation forces, produced by a focused rotational elliptical Laguerre–Gaussian correlated Schell-model (ELGSM) beam, on the dielectric particles of different refractive indices in the Rayleigh scattering regime. It is found that through a judicious modulation of the initial spatial coherence width and the beam order of the correlation function of the rotational ELGSM beam, the particles with higher refractive index (compared with the ambient) can be trapped along an elliptical ring centered at the focus, the particles with lower refractive index, at the same time, will be trapped at the focal point. Our results also show that the trapping area/range can be modulated by structuring the correlation function of the beam. By comparing the gradient, scattering, Brownian, and gravity forces acting on the particles, the trapping stability is analyzed. Our results indicate that the coherence structure engineering can be used as an alternative approach to modulate the symmetry of the optical trapping area.

我们分析了由聚焦旋转椭圆Laguerre-Gaussian相关Schell模型（ELGSM）光束在瑞利散射体制中不同折射率的介电粒子上产生的光辐射力。发现通过明智地调制初始空间相干宽度和旋转ELGSM光束的相关函数的光束阶数，具有较高折射率（与周围环境相比）的粒子可以沿着以圆环为中心的椭圆环捕获。聚焦时，折射率较低的粒子将同时被捕获在焦点处。我们的结果还表明，可以通过构造光束的相关函数来调节陷获面积/范围。通过比较作用在粒子上的梯度，散射，布朗和重力，分析了诱捕稳定性。我们的结果表明，相干结构工程可以用作替代方法来调制光学陷阱区域的对称性。