Broadband Perfect Absorber Based on TiN-Nanocone Metasurface

Abstract

Based on an integrated array of refractory titanium nitride (TiN), a metasurface perfect absorber (MPA) in the visible-to-near infrared (NIR) band is reported. The systematic and detailed simulation study of the absorption of the MPA is performed with the finite-different time-domain (FDTD) method. Tailoring the structure, the MPA realizes as high an average as 99.6% broadband absorption, ranging from 400 nm to 1500 nm. The broadband perfect absorption can be attributed to localized surface plasmonic resonance (LSPR), excited by the continuous diameter evolution from the apex to the base of the nanocone, and the gap plasmons excited among the nanocones, as well as in the spacer layer at longer wavelengths. Particularly, the coupling of the resonances is essentially behind the broadening of the absorption spectrum. We also evaluated the electric field intensity and polarization-dependence of the nanocone MPA to offer further physical insight into light trapping capability. The MPA shows about 90% average absorption even at an oblique incidence up to 50°, which improves the acceptance capability of light-harvesting system applications. This unique design with the TiN nanocone array/aluminium oxide (Al2O3)/TiN structure shows potential in imminent applications in light trapping and thermophotovoltaics.

Phase Change Metasurfaces by Continuous or Quasi-Continuous Atoms for Active Optoelectronic Integration

“…Furthermore, to conquer the narrow band nature of early MIM absorber, broadband absorption was realized by the hybridized design of multiple meta-atoms [ 124 ]. To name a few, exquisite schemes by Luo’s group and others were used to construct the extremely broadband perfect absorption, e.g., dispersion engineering [ 1 , 125 , 126 ], the impedance matching [ 127 ] and diffraction/interference engineering [ 7 , 8 , 128 ] etc.…”

“…In this situation, photonic metasurfaces show more prospects and outperform their volumetric versions mainly due to the ultra-thin and easy-to-integrate characteristics. Therefore, a plethora of meta-devices are demonstrated for both amplitude [ 1 ] and phase regulation [ 2 ], from the visible to terahertz (THz) and microwave range, such as ideal frequency selection [ 3 , 4 , 5 ], perfect absorption [ 6 , 7 , 8 , 9 ], beam steering or deflection [ 10 , 11 ], flat lensing [ 12 , 13 ], vortex beam generation [ 14 , 15 , 16 ], optical activity [ 17 , 18 ], holography [ 19 , 20 , 21 ], 3D color holography [ 22 , 23 ] and nonlinear effect [ 24 , 25 ] etc.…”

Broadband Absorption Based on Thin Refractory Titanium Nitride Patterned Film Metasurface

“…Various MPAs based on TiN achieve near-perfect absorption based on morphologies such as square, disk, cone or truncated-cone, tapered multilayer stacks, nanopillar, etc. [20,[27][28][29][30][31][32] While some of the metasurface designs are difficult to fabricate including many layers or complicated morphology, others cannot achieve perfect absorption bandwidth.…”

High-temperature ultra-broad UV–MIR high-efficiency absorber based on double ring-shaped titanium nitride resonators

“…The TiN based perfect absorbers, including square-ring aray, nanodisk array were firstly studied with high absorption limited in the visible regime [16,17]. More complicated TiN nanostructures, such as TiN 3D-truncated nanopillars and nanocones were proposed to realize broad absorption in the visible and near-infrared (NIR) regions [18,19]. Then, some absorbers were proposed to efficiently absorb the incident waves in the ultraviolet to NIR ranges [20][21][22].…”