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arXiv · 2204.06844

Second-harmonic generation from singular metasurfaces

Fan Yang·Cristian Ciracì
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Abstract

We present a theoretical study of second-harmonic generation from a singular metasurface. The singular metasurfaces strongly interact with the incident light, where the large field enhancement forms an intense surface polarization that generates the second-harmonic field. By using transformation optics, the calculation of nonlinear optical response is converted from the metasurface frame to that of a simple slab geometry, largely reducing the complexity of the problem. In addition, the singular metasurface exhibits a weak dependence on the incident angle of light, which can be potentially used as an all-angle device for harmonic generations. Finally, we study the symmetry dependence of second-harmonic generation in the far field for the singular metasurface and show how to enhance the conversion efficiency under normal incidence by breaking the surface inversion symmetry.

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Fan Yang, Cristian Ciracì. 2022-04-14. Second-harmonic generation from singular metasurfaces. https://doi.org/10.1103/physrevb.105.235432

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