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Abstract Metasurfaces have drawn considerable attentions for their revolutionary capability of tailoring the amplitude, phase, and polarization of light. By integrating the nonlinear optical processes into metasurfaces, new wavelengths are introduced as an extra degree of freedom for further advancing the device performance. However, most of the existing nonlinear plasmonic metasurfaces are based on metallic nanoantennas as meta‐atoms, suffering from strong background transmission, low laser damage threshold and small nonlinear conversion efficiency. Here, Babinet‐inverted plasmonic metasurfaces made of C‐shaped nanoapertures as meta‐atoms are designed and demonstrated to solve these issues. Rotation‐gradient nonlinear metasurfaces are further constructed for producing spin‐selective second‐harmonic vortex beams with the orbital angular momentum (OAM) and beam diffraction angle determined by both the spin states of the fundamental wave and second‐harmonic emission. The results enable new types of functional metasurface chips for applications in spin, OAM, and wavelength multiplexed optical trapping, all‐optical communication, and optical data storage.
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Bi-encoded metasurfaces for the infrared spectral range
Plasmonic metasurfaces composed of arrays of rectangular metallic bars are well known for their strong optical response in the infrared spectral range. In this study, we explore the polarization sensitivity of plasmonic metasurfaces for encoding information. The polarization-sensitive optical response depends strongly on the orientation of the metallic bars allowing the encoding of information into the metasurface. Here we demonstrate that a 2-dimensional polarization encoded metasurface can be obtained by using mask-less two-photon polymerization techniques. This novel approach for the fabrication of plasmonic metasurfaces enables the rapid prototyping and adaptation of polarization sensitive metasurfaces for the encoding of multiplexed images.
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- PAR ID:
- 10448468
- Editor(s):
- Digonnet, Michel J.; Jiang, Shibin
- Date Published:
- Journal Name:
- SPIE OPTO
- Volume:
- 12417
- Page Range / eLocation ID:
- 124170L
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1117/12.2661109
