Low-Contrast Dielectric Metasurface Optics
| Autor: | Alan Zhan, Shane Colburn, Rahul Trivedi, Taylor K. Fryett, Christopher M. Dodson, Arka Majumdar |
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| Rok vydání: | 2016 |
| Předmět: |
Diffraction
Materials science FOS: Physical sciences Physics::Optics 02 engineering and technology Dielectric 01 natural sciences 010309 optics chemistry.chemical_compound Planar Optics 0103 physical sciences Miniaturization Electrical and Electronic Engineering Image sensor High-refractive-index polymer business.industry 021001 nanoscience & nanotechnology Atomic and Molecular Physics and Optics Electronic Optical and Magnetic Materials Silicon nitride chemistry 0210 nano-technology business Beam (structure) Optics (physics.optics) Physics - Optics Biotechnology |
| Zdroj: | Scopus-Elsevier |
| ISSN: | 2330-4022 |
| DOI: | 10.1021/acsphotonics.5b00660 |
| Popis: | The miniaturization of current image sensors is largely limited by the volume of the optical elements. Using a sub-wavelength patterned quasi-periodic structure, also known as a metasurface, one can build planar optical elements based on the principle of diffraction. However, it was believed that high refractive index materials are required for metasurface optics. Here, we show that one can employ the design principles of a metasurface even with low contrast materials, such as silicon nitride. We validate our theory by fabricating and experimentally characterizing several silicon nitride based lenses and vortex beam generators . The fabricated lenses achieved beam spots of less than 1 {\mu}m with numerical apertures as high as ~ 0.75. A transmission efficiency of 90% and focusing efficiency of 40% in the visible regime was observed. Our results pave the way towards building low-loss metasurface based optical elements at visible frequencies using low contrast materials. Comment: 6 figures |
| Databáze: | OpenAIRE |
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