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arXiv · 1611.04351

Adding a spin to Kerker's condition: arbitrary scattering direction tuning of nano-antennas with designed excitation

Lei Wei·Nandini Bhattacharya·H. Paul Urbach
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Abstract

We describe a method to control the directional scattering of a high index dielectric nanosphere, which utilizes the unique focusing properties of an azimuthally polarized phase vortex and a radially polarized beam to independently excite insde the nanosphere a spinning magnetic dipole and a linearly polarized electric dipole mode normal to the magnetic dipole. We show that by simply adjusting the phase and amplitude of the field on the exit pupil of the optical system, the scattering of the nanosphere can be tuned to any direction within a plane and the method works over a broad wavelength range.

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Lei Wei, Nandini Bhattacharya, H. Paul Urbach. 2016-12-05. Adding a spin to Kerker's condition: arbitrary scattering direction tuning of nano-antennas with designed excitation. https://doi.org/10.1364/ol.42.001776

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