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arXiv · 1809.01755

Lorenz-Mie scattering of focused light via complex focus fields: an analytic treatment

Rodrigo Gutiérrez-Cuevas·Nicole J. Moore·Miguel A. Alonso
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Abstract

The Lorenz-Mie scattering of a wide class of focused electromagnetic fields off spherical particles is studied. The focused fields in question are constructed through complex focal displacements, leading to closed-form expressions that can exhibit several interesting physical properties, such as orbital and/or spin angular momentum, spatially-varying polarization, and a controllable degree of focusing. These fields constitute complete bases that can be considered as nonparaxial extensions of the standard Laguerre-Gauss beams and the recently proposed polynomials-of-Gaussians beams. Their analytic form turns out to lead also to closed-form expressions for their multipolar expansion. Such expansion can be used to compute the field scattered by a spherical particle and the resulting forces and torques exerted on it, for any relative position between the field's focus and the particle.

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Rodrigo Gutiérrez-Cuevas, Nicole J. Moore, Miguel A. Alonso. 2018-09-05. Lorenz-Mie scattering of focused light via complex focus fields: an analytic treatment. https://doi.org/10.1103/physreva.97.053848

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