Study On Interaction Scattering Properties Of Multi-object Illuminated By Shaped Gaussian Beam

Study on interaction scattering properties of multi-object illuminated by shaped Gaussian beam is of significant academic value and extensive applications in many fields. As multi-object in the plane wave have been fully studyed by many researches and the typical single object in the shaped Gaussian beam are also been studied, the main problem are focus on the multi-object scattering properties on the multi-object in the shaped Gaussian beam. With the development of naroparticle laser technology and the single molecule detection, this problem became the hot point of particle scattering field.The main aim and the results of this paper are as follows:1.Rigorous analytical expressions of multiple electromagnetic scattering for the scattered and inner field of the two spheres are derived. Based on the boundary conditions and the orthogonally properties of the spherical vector wave functions, the interactive coupled linear equations of multi-object in the plane wave are constructed. A more stable and accurate equations for two spheres scattering are proposed by using the spherical Bessel function and the spherical Hankel function and its derivative form especially in the large particle size parameter case. As the direct matrix converse is avoided, the computational results became more generous.2. The shaped Gaussian beam expanding coefficients in different time dependence term are studied. And the symmetric relationship of the Gaussian beam in these two cases is discussed. Different kinds of computational method of translation coefficients of spherical vector wave functions are compared and analyzed. The interaction electromagnetic scattering coefficients of two spheres in the shaped Gaussian beam are derived. And the construction method of the interference interaction equations of cluster spheres in a general case illuminated by the shaped beam is presented. When the beam waist radius is large enough compared with the radius of the particle and the incident wave length the shaped Gaussian beam incident case is proved may be reduced to that of plane wave incident case. A matrix expression of multi-object in the shaped Gaussian beam are propounded, some numerical results are presented.3. Base on the expanded boundary condition method, a particular solution of random rotational symmetrical particle surface is studied. As a finite cylinder as an example, we presented the formula of its scattering transformation matrix. Some preliminary numerical results are presented. The numerical results are compared with the results obtained by completely independent FDTD method.