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arXiv · 1605.07208

Broadband, Polarization-insensitive and Wide-angle Optical Absorber based on Fractal Plasmonics

Ali Eshaghian·Sajjad AbdollahRamezani·Ata Chizari·Amin Khavasi
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Abstract

In this paper, a plasmonic absorber consisting of a metal-dielectric-metal stack with a top layer of Sierpinski nanocarpet is theoretically investigated. Such compact absorber depicts broadband angle-independent behavior over a wide optical wavelength range ($400-700$ nm) and a broad range of angles of light incidence ($0-80^{\circ}$). Including several feature sizes, such fractal-like structure shows widely strong extinction ($85-99$%) response for either transverse electric or magnetic polarization states under normal incidence. Underlying mechanisms of absorbance due to excited surface plasmon modes as well as electric/magnetic dipole resonances are well revealed by investigating electric field, magnetic field and current distributions. The proposed absorber opens a path to realize high-performance ultrathin light trapping devices.

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Ali Eshaghian, Sajjad AbdollahRamezani, Ata Chizari, Amin Khavasi. 2016-05-23. Broadband, Polarization-insensitive and Wide-angle Optical Absorber based on Fractal Plasmonics. https://arxiv.org/abs/1605.07208

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