Near-perfect broadband absorption from hyperbolic metamaterial nanoparticles

167

107

and their potential applications in various fields, including optical waveguiding, imaging, ultrasensitive optical sensing, and electromagnetic cloaking.Among the different types of optical metamaterials proposed and demonstrated to date, there is one class of highly anisotropic metamaterials which exhibit hyperbolic (or indefinite) dispersions, depending on their effective electric tensors (here, we only consider nonmagnetic media with unit magnetic tensors). Such hyperbolic metamaterials (HMMs) have reached the ultra-anisotropic limit of traditional uniaxial crystal and lead to dramatic changes for the light propagation behaviors. [12][13][14][15][16] Compared with other optical metamaterials, like chiral [17,18] and split ring resonator-based metamaterials, [19,20] HMMs have advantages of relative ease of fabrication at optical frequencies, broadband nonresonant and 3D bulk responses, and flexible wavelength tunability. As a result, HMMs have attracted widespread interest and become a good multifunctional platform for many exotic applications, such as optical negative refraction and light beam steering, [12,[21][22][23][24][25][26][27][28] subdiffraction-limited imaging and nanolithography, [29][30][31][32][33][34][35][36][37][38][39][40][41][42][43][44][45] spontaneous and thermal emission engineering, [71][72][73][74][75][76][77][78][79][80] ultrasensitive optical, biological, and chemical sensing, [81][82][83][84][85][86][87][88][89] omnidirectional and broadband optical absorption. [90][91][92][93] On the other hand, ultrathin metasurfaces, which comprise a class of planar optical metamaterials with many subwavelength structural units, have attracted much attention due to their ability of locally controlling the phase, amplitude, and polarization of light at the interface between two natural materials. [94][95][96][97] 2D planar metasurfaces have many advantages over bulk metamaterials, including simplifying the fabrication and integration process, reducing energy loss, and being compatible with other photonics devices. In this context, as an efficient surface wave modulation platform, hyperbolic metasurfaces (HMSs) with in-plane hyperbolic dispersions have a potential influence on the development of on-chip planar photonic devices. [95,98] In this review, we first discuss the dispersions and realizations of hyperbolic media. Then, we review the recent achievements of various optical applications based on 3D bulk HMMs and 2D planar HMSs. It should be stressed that, although some application scenarios for 3D HMMs and 2D HMSs are analogous, in fact they are not equal to each other because additional constrains will be introduced on the surface wave as the dimensionality degraded, which is accompanied by fancy in-plane Recent advances in nanofabrication and characterization technologies have spurred many breakthroughs in the field of optical metamaterials and metasurfaces that provide novel ways of manipulating light interaction in a well controllable manner. Among these artificial nanostructured materials, ...

Section: D Bulk Hyperbolic Metamaterialsmentioning

confidence: 99%

Section: D Bulk Hyperbolic Metamaterialsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Hyperbolic Metamaterials and Metasurfaces: Fundamentals and Applications

Huo

Zhang

Liang

et al. 2019

167

107

“…With the well‐optimized dimensions (i.e., 600 nm period, 400 nm‐thick top Ni, 100 nm‐thick SiO 2 , 0.85 lateral filling ratio, and enough thick Ni substrate), >90% incident light are absorbed by this modified MDM structure for both polarization from 300 to 1000 nm, wherein absorption effects at short (≈450 nm) and long (≈1000 nm) wavelengths are recognized as the cavity resonance within the hollow regime of the concave grating and magnetic polaritons (i.e., LSPRs), respectively. Considering the wide variety of effects that can absorb light, such as grating diffraction, waveguiding, F–P resonance, PSPRs, LSPRs, etc., this basic idea further enriches the broadband absorber designs so that can satisfy different requirements . Although additional resonators allow flexibilities in selecting desired absorption band positions, most structured described above require delicate resonant cavities, which significantly increases the fabrication complexity, thereby hindering their practical applications.…”

Section: Broadband Perfect Absorbersmentioning

confidence: 99%

Engineering Light at the Nanoscale: Structural Color Filters and Broadband Perfect Absorbers

Lee

et al. 2017

161

121

Recent advances in fabrication and processing methods have spurred many breakthroughs in the field of nanostructures that provide novel ways of manipulating light interaction on a well controllable manner, thereby enabling a wide variety of innovative applications. Structural colors have shown great promise as an alternative for existing colorant‐based filters due to their noticeable advantages, which open up diverse potential applications such as energy‐efficient displays, ultrahigh‐resolution imaging, ultrahigh‐sensitivity biosensors, and building‐integrated photovoltaics. Broadband perfect absorbers, which exploit extraordinary optical phenomena at subwavelength scale, have also received increasing attention due to their capability of improving efficiency and performance characteristics of various applications including thermoelectrics, invisibility, solar‐thermal‐energy harvesting, and imaging. This review highlights some recent progress in these two related fields. The structural colors based on optical resonances in thin‐film structures, guided‐mode resonances in slab waveguide gratings, and surface plasmon resonances in plasmonic nanoresonators are described. Representative achievements associated with the broadband perfect absorbers, which include schemes employing highly absorbing media, multi‐cavity resonances, and broadband impedance matching are investigated.

“…[ 5,6 ] In recent years, significant efforts have been made in developing selective solar absorber coatings for mid‐temperature (370 K < T < 650 K) [ 7 ] to high‐temperature ( T > 650 K) applications. [ 8 ] The popular designs include plasmonic metamaterials, [ 9 ] non‐resonant carbon‐based structures, [ 10,11 ] and metal‐dielectric composites such as, MoSi 2 ‐Si 3 N 4 , [ 12 ] W‐WAlN‐WAlON‐Al 2 O 3 , [ 13 ] and WNi‐Al 2 O 3 . [ 8 ] Nevertheless, the tedious lithographic techniques to fabricate metamaterials, high infrared emissivity of carbon materials, and limited thermal/oxidation tolerance of multilayer cermet impede their utilization in real applications.…”

Section: Introductionmentioning

confidence: 99%

Refractory Ultrathin Nanocomposite Solar Absorber with Superior Spectral Selectivity and Thermal Stability

Raza

Alketbi

Devarapalli

et al. 2020

Highly efficient solar–thermal energy conversion requires refractory absorbers harnessing full spectrum of sunlight, minimal thermal emission, and structural stability at higher operating temperatures. Herein, an ultrathin ultrabroadband omnidirectional silicon carbide–tungsten (SiC‐W) refractory nanocomposite is fabricated by high‐throughput co‐sputtering with superior thermal and oxidation stability. The as‐fabricated SiC‐W nanocomposite (78 nm) deposited on tungsten layer with top anti‐reflective film exhibits high solar absorptance of 95.45% in the wide range of 250–2500 nm with thermal emittance below 0.05 at ambient temperature. The ultrabroadband absorption is achieved by plasmonic resonances triggered by self‐formed tungsten nanoclusters in the range of 500–1500 nm combined with SiC intrinsic absorption below λ < 500 nm. SiC as diffusion barrier also prevents interlayer diffusion and oxidation of tungsten nanoclusters to achieve superior thermal/oxidation stability, when annealed at 900 K (air) and 1050 K (vacuum). This work demonstrates outstanding capability of refractory nanocomposites in high‐performance solar thermal technologies for both terrestrial and space environments.