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Systematic control of Raman scattering with topologically induced chirality of light

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 نشر من قبل Xiao Liu
 تاريخ النشر 2021
  مجال البحث فيزياء
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Stokes Raman scattering is known to be a particularly robust nonlinearity, occurring in virtually every material, with spectra defined by the material and strengths dependent on the material as well as light intensities. This ubiquity has made it an indispensable tool in spectroscopy, but also presents itself as a stubborn source of noise or parasitic emission in several applications. Here, we show that orbital angular momentum carrying light beams experiencing spin-orbit interactions can fundamentally alter the selection rules for Raman scattering. This enables tailoring its spectral shape (by over half the Raman shift in a given material) as well as strength (by about 100 times) simply by controlling the topological charge of light, which is a capability of utility across the multitude of applications where modulating Raman scattering is desired.

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