论文标题
光学镊子中球体簇的布朗动力学模拟
Brownian dynamics simulations of sphere clusters in optical tweezers
论文作者
论文摘要
在计算上对光学镊子中波长大小的非球形颗粒的行为进行建模可以洞悉捕获平衡的存在和稳定性以及对此类颗粒的光学操纵。在这里，我们报告了非球形颗粒的布朗动力学模拟，这些模拟介绍了详细的光学，流体动力和热相互作用。我们使用$ t $ -matrix形式主义来计算焦力激光束在波长大小球体的簇上施加的光学力和扭矩，并且我们结合了捕获簇的各向异性布朗尼运动的详细扩散量。对于大小与波长相当或大的两个球形簇，我们观察到椭圆极偏光束中的光动力效应。我们还证明，对于高度不对称的手性七个球体，存在多个捕获平衡。我们的模拟可能会导致有关光学诱捕和操纵的实用建议，以及对潜在物理学的更深入的理解。
Computationally modeling the behavior of wavelength-sized non-spherical particles in optical tweezers can give insight into the existence and stability of trapping equilibria as well as the optical manipulation of such particles more broadly. Here, we report Brownian dynamics simulations of non-spherical particles that account for detailed optical, hydrodynamic, and thermal interactions. We use a $T$-matrix formalism to calculate the optical forces and torques exerted by focused laser beams on clusters of wavelength-sized spheres, and we incorporate detailed diffusion tensors that capture the anisotropic Brownian motion of the clusters. For two-sphere clusters whose size is comparable to or larger than the wavelength, we observe photokinetic effects in elliptically-polarized beams. We also demonstrate that multiple trapping equilibria exist for a highly asymmetric chiral cluster of seven spheres. Our simulations may lead to practical suggestions for optical trapping and manipulation as well as a deeper understanding of the underlying physics.
