Scattering of chiral particles by dual high-order circularly symmetric Bessel beams

This paper explores the interaction between dual circular symmetric higher-order Bessel beams (CSBBs) and chiral particles using the generalized Lorenz-Mie Theory (GLMT). By applying the vector superposition theorem, the distribution characteristics after the superposition of the dual beams are investigated. Boundary conditions are applied to calculate the near-field, internal field, and far-field radar cross-section (RCS) of the chiral particle under dual CSBBs illumination. In order to validate the precision of the theoretical model and the calculation approach, the RCS results are compared against two scenarios documented in the literature. Additionally, the numerical simulations offer a comprehensive examination of the characteristics of chiral particles in the near field, internal field, and far-field RCS, accompanied by an analysis of the effects of dual CSBBs and various parameters-including incidence angle, polarization angle, beam order, half-cone angle, chiral parameters, particle radius, and refractive index-on their scattering behavior. Research shows that when dual Bessel beams propagate in opposite directions, the field intensity forms a lattice structure, with the number of lattice points doubling linearly with the beam order. As the cone angle increases, the spatial width of the interference fringes narrows, and the intensity distribution becomes more concentrated near the center of the beam. Additionally, the increase in the chiral parameter significantly amplifies the variation of the internal field, affecting the focusing and distribution characteristics of the internal field in three-dimensional space. The incident angle primarily determines the symmetry of the electric field intensity distribution in both two-dimensional and threedimensional fields, thereby altering the beam's propagation pattern and its interaction with particles. Moreover, the increase in particle radius significantly enhances the local electric field intensity near the particle surface. This study provides theoretical insights into the interactions between dual circularly symmetric Bessel beams (CSBBs) and complex-shaped chiral cells, offering significant implications for applications in optical recognition, classification, and precise manipulation. It not only contributes to optimizing the construction of functional nanomaterials, enhancing the efficiency of complex microstructure fabrication, and advancing highprecision micro-nano technologies, but also significantly improves the selectivity of chiral chemical reactions. The research provides strong support for cutting-edge interdisciplinary exploration and technological innovation, with broad application prospects in fields such as biomedicine, materials science, micro-nano manufacturing, chemical analysis, and quantum optics.