Scattering of Bessel beam by arbitrarily shaped composite
particles with core–shell structure
Zhiwei Cui
n
, Yiping Han, Zhuyang Chen, Lu Han
School of Physics and Optoelectronic Engineering, Xidian University, Xi’ an 710071, China
article info
Article history:
Received 25 February 2014
Received in revised form
11 April 2014
Accepted 12 April 2014
Available online 19 April 2014
Keywords:
Scattering
Bessel beam
Composite particles
Surface integral equation
abstract
This study investigates the scattering of Bessel beam by composite particles with core–
shell structure. Specifically, the vector expressions of zero-th order Bessel beam that
satisfy well Maxwell's equations in combination with the rotation Euler angles are used to
represent the arbitrarily incident Bessel beams. An efficient numerical method based on
surface integral equations is introduced to formulate the scattering problems involving
arbitrarily shaped composite particles with core–shell structure. Solutions are performed
iteratively by using the multilevel fast multipole algorithm. The numerical results for
differential scattering cross sections of several selected composite particles are presented
and analyzed. This investigation is expected to provide useful guidance for techniques of
laser detection on particle, diagnosis, and manipulation.
& 2014 Elsevier Ltd. All rights reserved.
1. Introduction
Many particles encountered in nature or produced in
industrial processes, such as raindrops, ice crystals, biolo-
gical cells, dust grains, daily cosmetics, and aerosols in the
atmosphere, are often found to be inhomogeneous and can
be regarded as composite particles with core–shell structure.
The study of light scattering by these composite particles is
essential in a wide range of scientific fields and it has myriad
practical applications, including optical manipulation, particle
detection and discrimination, design of new optics devices, etc.
Over the past few decades, the scattering of plane wave
by various composite particles with core–shell structure
has been investigated extensively by many researchers. In
recent years, with the development of laser sources and
the tremendous expansion of their applications, there has
been a growing interest in the study of light scattering by
various core–shell composite particles illuminated by laser
beams. For the case of an incident focused Gaussian beam,
an early study was carried out by Khaled et al. [1]. In that
paper, they applied the T-matrix method to examine the
scattering of an off-axis Gaussian beam by a concentrically
layer ed sphere. Later , within the framework of the generalized
Lorenz–Mie theory (GLMT) [2],GouesbetandGréhan[3] , Han
et al. [4], Yan et al. [5], and Wang et al. [6,7] investigated
the scattering of an arbitrarily incident Gaussian beam by
an eccentrically layered sphere. Subsequently, Zhang and
Liao [8] adopted the GLMT to study the Gaussian beam
scattering by a spherical particle with a spheroidal inclu-
sion. Yan et al. [9] investigated the case of a spheroidal
particle with a spherical inclusion. In addition, Sun et al.
[10] constructed an analytic solution to the Gaussian beam
scattering by a conducting spheroid with a confocal dielec-
tric coating. Despite some studies, as reviewed herein,
have been carried out on the scattering of Gaussian beam
by several kinds of composite particles with core–shell
structure, these studies mainly focused on the cases of
regular composite particles. Recently, we introduced an
efficient numerical method based on surface integral
equations to characterize the scattering of an arbitrarily
Contents lists available at ScienceDirect
journal homepage: www.elsevier.com/locate/jqsrt
Journal of Quantitative Spectroscopy &
Radiative Transfer
http://dx.doi.org/10.1016/j.jqsrt.2014.04.007
0022-4073/& 2014 Elsevier Ltd. All rights reserved.
n
Corresponding author. Tel.: þ86 13484556749.
E-mail address: zwcui@mail.xidian.edu.cn (Z. Cui).
Journal of Quantitative Spectroscopy & Radiative Transfer 144 (2014) 108–116