Light scattering

About: Light scattering is a research topic. Over the lifetime, 37721 publications have been published within this topic receiving 861581 citations.

Effects of TiCl4 Treatment of Nanoporous TiO2 Films on Morphology, Light Harvesting, and Charge-Carrier Dynamics in Dye-Sensitized Solar Cells

Abstract: We report on the effects of treating TiO2 nanocrystalline films with different concentrations of TiCl4 (5–500 mM) on the film morphology, charge-carrier dynamics, and performance of dye-sensitized solar cells. Transport and recombination in the TiCl4-treated films were studied by frequency-resolved modulated photocurrent/photovoltage spectroscopies. These studies showed that, at a low TiCl4 concentration (5 mM), the electron diffusion coefficient in the annealed film increased. At intermediate TiCl4 concentrations (15–50 mM), the surface area of the films increased, resulting in an increase of light harvesting and overall power conversion efficiency. At a high TiCl4 concentration (500 mM), light scattering in the film in the long wavelength region of the visible spectrum was enhanced, but the averaged pore size of the film became narrower, resulting in slower transport and loss of cell performance.

Polymer stabilized liquid crystalline light modulating device and material

Abstract: A new liquid crystalline light modulating cell and material are characterized by liquid crystalline light modulating material of liquid crystal and polymer, the liquid crystal being a chiral nematic liquid crystal having positive dielectric anisotropy and including chiral material in an amount effective to form focal conic and twisted planar textures, the polymer being distributed in phase separated domains in the liquid crystal cell in an amount that stabilizes the focal conic and twisted planar textures in the absence of a field and permits the liquid crystal to change textures upon the application of a field. In one embodiment, the material is light scattering in a field-OFF condition and optically clear in a field-ON condition, while in another embodiment, the material is optically clear in a field-OFF condition and light scattering in a field-ON condition. In still another embodiment, the material exhibits stability at zero field in a colored, light reflecting state, a light scattering state and multiple stable reflecting state therebetween, as well as being optically clear in the presence of a field.

Multiple-scattering treatment for small-angle scattering problems

Abstract: Analytical explicit expressions have been derived for multiple-scattering effects under assumptions which are usually fulfilled in small-angle scattering. The expressions are used to evaluate quantitatively distortions of scattering patterns caused by multiple scattering. The distortions are discussed in terms of changes of the forward-scattering cross section, the radius of the gyration, the integrated intensity, the Porod region and Porod constant. In addition, the analytical expressions have been used to calculate the scattering cross section of the sample from scattering patterns which are strongly affected by multiple scattering.

Ultra-directional forward scattering by individual core-shell nanoparticles

Abstract: We study the angular scattering properties of individual core-shell nanoparticles that support simultaneously both electric and optically-induced magnetic resonances of different orders. In contrast to the approach to suppress the backward scattering and enhance the forward scattering relying on overlapping electric and magnetic dipoles, we reveal that the directionality of the forward scattering can be further improved through the interferences of higher order electric and magnetic modes. Since the major contributing electric and magnetic responses can be tuned to close magnitudes, ultra-directional forward scattering can be achieved by single nanoparticles without compromising the feature of backward scattering suppression, which may offer new opportunities for nanoantennas, photovoltaic devices, bio-sensing and many other interdisciplinary researches.

Regimes of surface roughness measurable with light scattering

Abstract: In this paper we summarize a number of previous experiments on the measurement of the roughness of metallic surfaces by light scattering. We identify several regimes that permit measurement of different surface parameters and functions, and we establish approximate limits for each regime. Using a straightforward criterion, we calculate that the smooth-surface regime, in which the angular distribution of scattered light is closely related to the power spectral density of the roughness, ranges over 0 < σ/λ ≲ 0.05, where σ is the rms roughness and λ is the opitcal wavelength. Above that the surfaceautocorrelation function may be calculated from a Fourier transform of the angular distribution over 0 < σ/λ ≲ 0.14. Then comes the specular regime where the specular beam can still be identified andmeasured over 0 < σ/λ ≲ 0.3. For all these regimes and for rougher surfaces too, the rms width of thescatter distribution is proportional to the rms slope of the surface.