Related papers: Light trapping in solar cells at the extreme coupl…
Excitations of MHz acoustic modes are studied numerically in 10-um-thick silicon disk membranes with a radius of 100 and 500 um actuated by an attached 1-um-thick (AlSc)N thin-film transducer. It is shown how higher-harmonic membrane modes…
Hydrogenated amorphous silicon alloy films are generally deposited by radio frequency plasma enhanced chemical vapor deposition (RF PECVD) technique on various types of substrates. Generally it is assumed that film quality remains unchanged…
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…
The absorption spectra of silicon nanowires (SiNW) are calculated using semi-empirical $sp^{3}d^{5}s^{*}$ tight binding (TB) and Density Functional Theory (DFT) methods. The role of diameter, wave function symmetry, strain and…
We report the absorption/transmission properties of thin copper films slightly below the percolation limit produced by laser ablation; these samples show randomly positioned islands. Two types of films are grown: in the first type, copper…
A new approach is introduced to significantly improve the performance of thermophotovoltaic (TPV) systems by using low-dimensional thermal emitters and photovoltaic (PV) cells. By reducing the thickness of both the emitter and the PV cell,…
We closely study the local amplifications of visible light on a thin dielectric slab presenting a sub-wavelength array of small, rectangular, bottom-closed holes. The high-quality Fabry-Perot resonances of eigen modes which vertically…
Surface lattice resonance supported on plasmonic nanoparticle arrays enhances light-matter interactions for applications such as photoluminescence enhancement. The photoluminescence process is enhanced through confining light beyond the…
Ultrathin solar cells reduce material usage and allow the use of lower-quality materials thanks to their one order of magnitude smaller thickness than their conventional counterparts. However, efficient photonic light-trapping is required…
We derive upper and lower bounds on the absorption of ultraintense laser light by solids as a function of fundamental laser and plasma parameters. These limits emerge naturally from constrained optimization techniques applied to a…
An electro-absorption optical modulator concept based upon a dual-graphene layer is presented. The device consists of a silicon-on-insulator waveguide upon which two graphene layers reside, separated by a thin insulating region. The lower…
The integration of two-dimensional (2D) periodic nanopattern defined by nanoimprint lithography and dry etching into aluminum induced crystallization (AIC) based polycrystalline silicon (Poly-Si) thin film solar cells is investigated…
The thermodynamic limit of photovoltaic efficiency for a single-junction solar cell can be readily predicted using the bandgap of the active light absorbing material. Such an approach overlooks the energy loss due to non-radiative…
We investigate p-mode absorption in a sunspot using SOHO/MDI high-resolution Doppler images. The Doppler power computed from a three and a half hour data set is used for studying the absorption in a sunspot. The result shows an enhancement…
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…
A simple perfect absorption structure is proposed to achieve the high efficiency light absorption of monolayer molybdenum disulfide (MoS 2 ) by the critical coupling mechanism of guided resonances. The results of numerical simulation and…
Thin-film solar cells that are considered as the second generation of solar cells are known for their low cost and acceptable efficiency. In this technology, semiconductor layers with a thickness of micrometer are deposited on thick enough…
We study oblique incident light absorption in opaque media with rough surfaces. An analytical approach with modified boundary conditions taking into account the surface roughness in metallic or dielectric films has been discussed. Our…
We develop a new approach to calculate the obtainable limit of photoconversion efficiency of tandem solar cells (SCs) and applied it to SCs with both vertical and lateral designs at AM0 and AM1.5 conditions. To get the maximum efficiency,…
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…