High-refractive-index (HRI) dielectric metasurfaces have attracted a lot of attention recently due to their advantages of low non-radiative losses and high melting temperatures. Silicon is one of feasible HRI materials that has been widely used in solar cells, photonic waveguides, and photon detectors. However, the band-gap ~ 1 eV makes the quantum efficiency of silicon low at near-infrared (NIR) wavelengths. In this work, a high absorptance device is proposed and realized by using amorphous silicon nanoantenna arrays (a-Si NA arrays) that suppress backward and forward scattering with engineered lattice resonance with Kerker effect. The overlap of electric dipole and magnetic dipole resonances is experimentally demonstrated. The absorptance of a-Si NA arrays increases 3-fold in the near-infrared (NIR) range in comparison to unpatterned silicon films. Nonradiating a-Si NA arrays can achieve high absorptance with a small resonance bandwidth (Q = 11.89) at wavelength 785 nm.
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