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Generation of tunable optical skyrmions on Skyrme-Poincare sphere

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 نشر من قبل Yijie Shen
 تاريخ النشر 2021
  مجال البحث فيزياء
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In recent time, the optical-analogous skyrmions, topological quasiparticles with sophisticated vectorial structures, have received an increasing amount of interest. Here we propose theortically and experimentally a generalized family of these, the tunable optical skyrmion, unveiling a new mechanism to transform between various skyrmionic topologies, including Neel-, Bloch-, and antiskyrmion types, via simple parametric tuning. In addition, Poincare-like geometric representation is proposed to visualize the topological evolution of tunable skyrmions, which we termed Skyrme-Poincare sphere, akin to the spin-orbit representation of complex vector modes. To generate experimentally the tunable optical skyrmions we implemented a digital hologram system based on a spatial light modulator, showing great agreement with our theoretical prediction.

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