In this paper, wide-angle infrared perfect absorption has been demonstrated by using a double-layer graphene strip grating coupled with silicon dioxide grating. Numerical simulation of the finite-difference time-domain method indicates that can be achieved due to effective impedance matching, and all incident electromagnetic energy is confined in Al 2 O 3 layer between silver substrate Dual-ban...

This paper proposes a novel design for a compact, high-isolation WCDMA indoor repeater antenna. The proposed antenna consists of a patch antenna and metamaterial absorber. The required WCDMA bandwidth is obtained by utilizing the coupling between the main and the parasitic patches. In addition, high isolation is achieved using the metamaterial absorber, which has an absorption of about 98% at 2...

Articles you may be interested in Structural and electronic modification of photovoltaic SnS by alloying Thin film photovoltaic cells are increasingly important for cost-effective solar energy harvesting. Layered SnS is a promising absorber material due to its high optical absorption in the visible and good doping characteristics. We use first-principles calculations based on density functional...

This work presents measured results demonstrating an uncooled infrared (IR) detector based on gallium nitride (GaN) micromechanical resonators. GaN-based photonic detectors are typically designed to operate in the ultraviolet (UV) regime as the absorption spectrum of wide-band gap GaN peaks at a wavelength of ~360 nm. In contrast, the transduction mechanism of the device presented in this work ...

In recent years, perovskite solar cells have been considerably developed, however the lead in the absorber MAPbI3 is a potential threat to the environment. To explore potential alternatives, the structural and electronic properties of MAGeX3 (X = Cl, Br, I) were investigated using different density functional theory methods, including GGA-PBE, PBE-SOC, HSE06 and HSE-SOC. The results implied tha...

Full description of an absorption band is complex, but approximate expressions can be used over limited ranges of absorber mole fraction, pressure and pathlength. It can be shown that the “non-overlapping line approximation” applies at ambient pressure and CO2 mole fraction over the short pathlengths found in LI-COR infrared gas analyzers (Wolfe and Zissis, 1978). This leads to a “scaling law” ...

The dissipative electromagnetic energy absorption of tailored metamaterials can be exploited to improve the spectral sensitivity and selectivity of thermal detectors. The desired detector characteristics are engineered by tuning the singleor multiband absorption by resonance frequency, magnitude, and spectral bandwidth, strongly depending on the geometrical design of metamaterials. Here, the op...

A subwavelength metamaterial perfect absorber (MPA) in optical communication band was proposed and tested using the finite-difference time-domain method. The is periodic comprises a top layer of diamond silicon surrounded by L-shaped gold on substrate. It can achieve dual-band absorption, one peaks band. By changing gap (g) between two adjacent pieces silicon, thickness (h) layer, resonance wav...

Thin film photovoltaic cells based on hybrid halide perovskite absorbers have emerged as promising candidates for next generation photovoltaics. Here, we have characterized and identified the defect energy distribution in the CH3NH3PbI3 perovskite using admittance spectroscopy, which reveals a deep defect state ∼0.16 eV above the valence band. According to theoretical calculations, the defect s...

We have developed an on-the-fly scanning spectrometer operating in the UV-visible and near-infrared that can simultaneously perform transmission and total reflectance measurements at the rate better than 1 sample per second. High throughput optical characterization is important for screening functional materials for a variety of new applications. We demonstrate the utility of the instrument for...