Topic
Diffraction efficiency
About: Diffraction efficiency is a research topic. Over the lifetime, 10320 publications have been published within this topic receiving 158298 citations.
Papers published on a yearly basis
Papers
More filters
TL;DR: This work investigates the diffraction efficiency of strong volume holograms in which the coupling parameter is several times that needed for maximum diffraction Efficiency and discusses the implications on photorefractive implementations of various neural network systems.
Abstract: We investigate the diffraction efficiency of strong volume holograms in which the coupling parameter is several times that needed for maximum diffraction efficiency. We discuss the implications of our findings on photorefractive implementations of various neural network systems.
51 citations
TL;DR: In this article, the authors performed a characterization of the diffraction efficiency of Bragg gratings written in liquid-crystalline composite materials by the interference pattern of two curing beams.
Abstract: We have performed a first characterization of the diffraction efficiency of gratings written in liquid-crystalline composite materials by the interference pattern of two curing beams. The grating fringes consist of polymer slices separated by films of continuous nematic phase. The dependence of the diffraction efficiency on temperature reveals a nonmonotonic behavior, with several maxima and minima. The shapes of curves are dependent on slight changes in the initial concentration of the nematic component of the mixture; the number of extrema increases with an increase of this concentration. The dependence of the diffraction efficiency on an applied external voltage also appears to be nonmonotonic: The shape depends on the sample’s temperature. Both switch-on and switch-off responses have been observed. The behavior of our gratings can be explained in the framework of the conventional Kogelnik theory for the diffraction efficiency of Bragg gratings.
51 citations
TL;DR: In this paper, the effects of finite beams and finite gratings on the performance of guided-mode resonant subwavelength gratings were characterized by using the rigorous boundary element method.
Abstract: The effects of finite beams and finite gratings on the performance of guided-mode resonant subwavelength gratings are characterized by using the rigorous boundary element method. The gratings are strongly modulated, have a finite number of periods, and are illuminated by normally incident Gaussian beams. Quantitative results are presented for silicon-on-sapphire resonant gratings and gallium arsenide-aluminum arsenide resonant gratings.
51 citations
TL;DR: In this article, the optical properties and phase change of a commonly used glass, quartz, were investigated before and after focused ion beam (FIB) bombardment with ion energy from 30 to 50 keV.
Abstract: Optical properties (transmission and refractive index) and phase change (from amorphous to crystal) of a commonly used glass, quartz, were investigated before and after focused ion beam (FIB) bombardment with ion energy from 30 to 50 keV. We found different influences of FIB bombardment on the optical properties and chemical structure of the quartz in the wavelength region of visible and near infrared, respectively. The quartz still can be used in the infrared wavelength for conventional optical applications. As an application example, an array of diffractive optical elements (DOEs) was directly fabricated on the quartz by the FIB milling. The measured diffraction efficiency of the DOEs is 83.5%, which is acceptable for practical use.
51 citations
TL;DR: In this article, a switchable grating based on chiral single walled carbon nano-tube (SWCNT) doped ferroelectric liquid crystals (FLCs) is presented.
Abstract: We present a switchable grating based on chiral single walled carbon nano-tube (SWCNT) doped ferroelectric liquid crystals (FLCs). The presence of SWCNTs improves the diffraction profile of the pure FLC. The diffraction efficiency, i.e., the ratio of intensities of first order and zero order maxima is more than 100% for the higher concentration of SWCNTs in pure FLC. This phenomenon has been explained by the decrease in ferroelectric domain periodicity, due to the doping of SWCNTs in pure FLC, and optical activity of the chiral SWCNTs. These gratings with very high diffraction efficiency may find application in many devices.
51 citations