In this work we theoretically reveal the huge local field enhancement in a so-called perfect plasmonic absorber. We study the power absorption of light in a planar grid modelled as an effective sheet with zero optical thickness. The key prerequisite of the total absorption is the simultaneous presence of both resonant electric and magnetic modes in the structure. We show that the needed level o...

The infrared spectra of amorphous films of Gap, GaAs, GaSb, InAs, and Ge prepared by sputtering have been measured from 10 to 4000 cm-1. The absorption spectra in the region of the “optical” phonon frequencies show similarities to the phonon density of states as deduced from Raman scattering but the absorption becomes much smaller a t low frequencies. It is shown that while the coupling constan...

A nonlinear forecasting method based on the reconstruction of a chaotic strange attractor from about 1.5 years of cloud absorption data obtained from half-hourly Meteosat infrared images was used to predict the behavior of the time series 24 h in advance. The forecast values are then used by a meteorological model for daily prediction of plume transport from the As Pontes 1400-MW power plant in...

Absorption coefficients of the carbon dioxide (CO2) were measured at atmospheric pressure and room temperature by photoacoustic technique with a cw, line-tunable, frequency stabilized CO2 laser. The CO2 laser spectrum of our system consists in 53 lines with wavelengths ranging from 9.2 μm to 10.8 μm and power levels below 5 W. Measured values of the CO2 absorption coefficients are typically of ...

The linear absorption spectra of GaP, TiO2, ZnSe, and ZnS are measured in their transparency range using a twocolor, excite-probe Z-scan. ZnS has the lowest absorption coefficient ( 10 5 cm ) in the wavelength range 840–900 nm, making it an excellent material for use as a luminescence extracting lens in semiconductor laser cooling experiments. Direct observation of two-photon absorption in ZnSe...

Organic solar cells have narrow absorption windows, compared to the absorption band of inorganic semiconductors. A possible way to capture a wider band of the solar spectrum—and thus increasing the power conversion efficiency—is using more solar cells with different bandgaps in a row, i.e., a multi-junction solar cell. We calculate the ideal material characteristics (bandgap combinations and ab...

A simple design of an ultrathin six-band polarization-insensitive terahertz perfect metamaterial absorber (PMMA) composed of a metal cross-cave-patch resonator (CCPR) placed over a ground plane was proposed and investigated numerically. The numerical simulation results demonstrate that the average absorption peaks are up to 95% at six resonance frequencies with high quality-factors (>65). In ad...

The temperature and salt dependencies of absorption by liquid water (H2O) and heavy water (D2O) were determined using a hyperspectral absorption and attenuation meter (WET Labs, AC-S). Sodium chloride (NaCl) was used as a proxy for seawater salts. There was no significant temperature (PsiT) or salt (PsiS) dependency of absorption at wavelengths <550 nm. At wavelengths >550 nm, PsiT exhibited pe...

In this paper, we present the simulation results on the absorption modification in a two-dimensional photonic crystal slab (2D PCS) structure, based on three-dimensional finite-difference time-domain technique (3D FDTD). Significantly enhanced absorption at defect level was obtained at surface normal direction in a single defect photonic crystal cavity, for both in-plane and vertical sources. A...

In order to implement an integrated optical quantum circuit, designing waveguides based on the quantum box is of prime importance. To do this we have investigated optical waveguide both with and without optical pumping. The rate of absorption and emission using an array of AlGaAs/GaAs quantum box core/shell structure in the optical waveguide with various pumping intensities has computed. By con...