We study the spiral spectra scattered off transparent dielectric spheres when probed by different Laguerre–Gaussianlight beams, carrying nested topological wavefront dislocations. We show that such scattering data may be employedto determine geometrical properties of the spheres, such as their position. The technique is a generalizationof standard Mie scattering, and it can be extended to study and to characterize nanospheres.

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