3D conical helix metamaterial-based isotropic broadband perfect light absorber

We present the design and fabrication of an isotropic broadband perfect light absorber in the near-infrared range using 3D metamaterials with a single resonator in the unit cell. The metamaterial resonator is comprised of a gold conical helix supported on a silicon pillar with back reflector realized on a silicon substrate. Simulations and experiments have demonstrated that the proposed absorber achieves a broad absorption band of more than 3 mu m in the 1.5-4.5 mu m wavelength range with an average absorbance of more than 90 %. The numerical and experimental analyses show that the proposed device can provide both incident angle and polarization independent operations, which further widens the application prospects of our device. (C) 2019 Optical Society of America under the terms of the OSA Open Access Publishing