Rigorous analysis of spheres in Gauss-Laguerre beams

Imperial College London, Londinium, England, United Kingdom
Optics Express (Impact Factor: 3.49). 11/2007; 15(20):13360-74. DOI: 10.1364/OE.15.013360
Source: PubMed


In this paper we develop a rigorous formulation of Gauss- Laguerre beams in terms of Mie scattering coefficients which permits us to quasi-analytically treat the interaction of a spherical particle located in the focal region of a possibly high numerical aperture lens illuminated by a Gauss-Laguerre beam. This formalism is used to study the scattered field as a function of the radius of a spherical scatterer, as well as the translation of a spherical scatterer through the Gauss-Laguerre illumination in the focal plane. Knowledge of the Mie coefficients provides a deeper insight to understanding the scattering process and explaining the oscillatory behaviour of the scattered intensity distribution.

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