Abstract

Electromagnetic scattering of a Gaussian beam by an off-axis dielectric sphere is treated by the sum-of-waves formulation, which is inherent in Lorenz–Mie theory. Each “wave” is a spherical eigenvector, defined in the natural frame of the scatterer, and the coefficient of that wave is the “wave amplitude.” Decomposition of the beam into homogeneous plane waves lays the ground for a synthesis of the wave amplitudes, which is done by an integration over the polar angle that defines the direction of propagation of the plane-wave constituents of the beam. Concise analytical results are developed for (a) the electric-field intensity in every part of space, (b) the bistatic and monostatic radar cross sections of the scatterer, and (c) the power extracted from the beam by scattering and absorption. Numerical calculations are made for a spherical glycerol droplet of radius 1.5 μm that is excited by an adjacent, infrared, Gaussian beam of wavelength 1.1424 μm and spot size 2 μm. The numerical application manifests (a) how the beam is coupled with the droplet and (b) the effect of the droplet on the power intercepted by a receiver-end fiber placed on the beam axis, beyond the focal plane. Comparisons to numerical results obtained by a finite-element method software (a) validate the sum-of-waves theory, (b) evaluate the performance of the code implementing that theory, and, succinctly, (c) manifest the limits of the plane-wave decomposition of the beam.

© 2017 Optical Society of America

Full Article  |  PDF Article
OSA Recommended Articles
Study of interactive scattering by clusters of spheres

M. P. Ioannidou, N. C. Skaropoulos, and D. P. Chrissoulidis
J. Opt. Soc. Am. A 12(8) 1782-1789 (1995)

Internal and external electromagnetic fields for on-axis Gaussian beam scattering from a uniaxial anisotropic sphere

Zhen-sen Wu, Qiong-kun Yuan, Yong Peng, and Zheng-jun Li
J. Opt. Soc. Am. A 26(8) 1778-1787 (2009)

References

You do not have subscription access to this journal. Citation lists with outbound citation links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Cited By

You do not have subscription access to this journal. Cited by links are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Figures (10)

You do not have subscription access to this journal. Figure files are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Tables (3)

You do not have subscription access to this journal. Article tables are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Equations (36)

You do not have subscription access to this journal. Equations are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription

Metrics

You do not have subscription access to this journal. Article level metrics are available to subscribers only. You may subscribe either as an OSA member, or as an authorized user of your institution.

Contact your librarian or system administrator
or
Login to access OSA Member Subscription