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Enhanced second-harmonic generation with structured light in AlGaAs nanoparticles governed by magnetic response

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 نشر من قبل Yuri Kivshar
 تاريخ النشر 2018
  مجال البحث فيزياء
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We employ structured light for the second-harmonic generation from subwavelength AlGaAs nanoparticles that support both electric and magnetic multipolar Mie resonances. The vectorial structure of the pump beam allows addressing selectively Mie-resonant modes and control the strength of the generated nonlinear fields. We observe experimentally the enhancement of the second-harmonic generation for the azimuthally polarized vector beams near magnetic dipole resonance, and match our observations with the numerical decomposion of the Mie-type multipoles for the fundamental and generated second-harmonic fields



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