相关论文: Total absorption of visible light in ultra-thin we…
Enabling perfect light absorption in ultrathin materials promises the development of exotic photonic devices. Here we demonstrate new strategies that can provide capabilities to rationally design ultrathin (thickness <…
Understanding the maximal enhancement of solar absorption in semiconductor materials by light trapping promises the development of affordable solar cells. However, the conventional Lambertian limit is only valid for idealized material…
Absorption of microwave by metallic conductors is exclusively inefficient, though being natively broadband, due to the huge impedance mismatch between metal and free space. Reducing the thickness to ultrathin conductive film may improve the…
We propose a design for an universal absorber, characterized by a resonance frequency that can be tuned from visible to microwave frequencies independently of the choice of the metal and the dielectrics involved. An almost resonant perfect…
We observe near 100 % absorption of light in intense ultrashort laser plasma interaction in a metal coated (Au on glass) sub-lambda grating structure under suitable conditions and the subsequent 'hot' electron generation from the grating…
We present an ultra broadband thin-film infrared absorber made of saw-toothed anisotropic metamaterial. Absorbtivity of higher than 95% at normal incidence is supported in a wide range of frequencies, where the full absorption width at half…
The optical absorption of nanoscale thickness semiconductor films on top of light-trapping structures based on optical interference effects combined with spectrum-splitting structures is theoretically investigated. Nearly perfect absorption…
In this paper, we calculate the material specific absorption accurately using a modal method by determining the integral of the Poynting vector around the boundary of a specific material. Given that the accuracy of our method is only…
Reducing device volume is one of the key requirements for advanced nanophotonic technologies, however this demand is often at odds with designing highly absorbing elements which usually require sizeable thicknesses, such as for detector and…
In this work, a metamaterial selective solar absorber made of nanostructured titanium gratings deposited on an ultrathin MgF2 spacer and a tungsten ground film is proposed and experimentally demonstrated. Normal absorptance of the…
We consider light absorption in a germanium grating placed on top of photonic-crystalline substrate. Such a system supports an optical Tamm state decoupled from the continuous spectrum with its frequency within the photonic band gap. We…
The photosensitivity of silicon is inherently very low in the visible electromagnetic spectrum, and it drops rapidly beyond 800 nm in near-infrared wavelengths. Herein, we have experimentally demonstrated a technique utilizing…
The design and fabrication of a metal-dielectric-metal absorber that achieves strong absorption from the ultraviolet (UV) to the near-infrared (near-IR) spectrum are presented. The proposed nanostructure consists of a periodic titanium (Ti)…
This paper presents modelled results for optical absorption in ultra-thin films of nickel, gold and silver across the solar spectrum. It is found in the case of nickel there is an optimum thickness for maximum solar absorption around…
Broadband absorption in the visible spectrum is essential in optoelectronic applications that involve power conversion such as photovoltaics and photocatalysis. Most ultrathin broadband absorbers use parasitic plasmonic structures that…
Thermal detectors are a cornerstone of infrared (IR) and terahertz (THz) technology due to their broad spectral range. These detectors call for suitable broad spectral absorbers with minimalthermal mass. Often this is realized by plasmonic…
In this paper, mu-near-zero (MNZ) metamaterials are utilized to achieve an ultrathin absorber with a thickness of only about one percent of the operating wavelength. The metamaterial absorber (MA) is made of double-layered metallic spiral…
The maximal absorption rate of ultra-thin films is 50% under the condition that the tangential electric (or magnetic) field is almost constant across the film in symmetrical environment. However, with certain reflectors, the absorption rate…
Optical absorption is one of fundamental light-matter interactions. In most materials, optical absorption is a weak perturbation to the light. In this regime, absorption and emission are irreversible, incoherent processes due to strong…
One-dimensional lamellar gratings allow a particularly efficient way for solving Maxwell's equations by expanding the electromagnetic field in the basis of exact eigenmodes of the Helmholtz equation. Then, the solution can be expressed…