scholarly journals Optical Properties of Porous Alumina Assisted Niobia Nanostructured Films–Designing 2-D Photonic Crystals Based on Hexagonally Arranged Nanocolumns

Micromachines ◽  
2021 ◽  
Vol 12 (6) ◽  
pp. 589
Author(s):  
Andrei Pligovka ◽  
Alexander Poznyak ◽  
Małgorzata Norek
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Effective Refractive Index ◽  
Porous Alumina ◽  
Spectral Characteristics ◽  
Two Dimensions ◽  
Fdtd Simulation ◽  
Nanostructured Films ◽  
Glass Substrates ◽  
Effective Medium Models

Three types of niobia nanostructured films (so-called native, planarized, and column-like) were formed on glass substrates by porous alumina assisted anodizing in a 0.2 M aqueous solution of oxalic acid in a potentiostatic mode at a 53 V and then reanodizing in an electrolyte containing 0.5 M boric acid and 0.05 M sodium tetraborate in a potentiodynamic mode by raising the voltage to 230 V, and chemical post-processing. Anodic behaviors, morphology, and optical properties of the films have been investigated. The interference pattern of native film served as the basis for calculating the effective refractive index which varies within 1.75–1.54 in the wavelength range 190–1100 nm. Refractive index spectral characteristics made it possible to distinguish a number of absorbance bands of the native film. Based on the analysis of literature data, the identified oxide absorbance bands were assigned. The effective refractive index of native film was also calculated using the effective-medium models, and was in the range of 1.63–1.68. The reflectance spectra of all films show peaks in short- and long-wave regions. The presence of these peaks is due to the periodically varying refractive index in the layers of films in two dimensions. FDTD simulation was carried out and the morphology of a potential 2-D photonic crystal with 92% (wavelength 462 nm) reflectance, based on the third type of films, was proposed.

scholarly journals Optical properties of AlN layers obtained by magnetron sputtering

2018 ◽  
Vol 36 (4) ◽  
pp. 717-721
Author(s):  
Piotr Potera ◽  
Grzegorz Wisz ◽  
Łukasz Szyller
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Magnetron Sputtering ◽  
Energy Gap ◽  
Optical Measurements ◽  
Transmission Spectra ◽  
Glass Substrates ◽  
Different Content

AbstractThe growth of AlN layers on glass substrates using magnetron sputtering method was performed and the grown layers were subjected to optical measurements. Transmission spectra of the layers grown at different content of N2 in the atmosphere were obtained. The transmission spectra as well as energy gap depended on N2 content. The annealing of the layers in air led to transmission changes and influenced energy gap and refractive index values.

Properties of TiO2 Thin Film Prepared by Sol-Gel Dip Coating

2015 ◽  
Vol 723 ◽  
pp. 528-531
Author(s):  
Jun Wang ◽  
Ling Yun Bai
Keyword(s):  
Thin Film ◽  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Band Gap ◽  
Optical Band Gap ◽  
Sol Gel ◽  
Dip Coating ◽  
Gel Method ◽  
Glass Substrates

TiO2 thin films were prepared on glass substrates by sol-gel method. The effect of withdraw speed on the thickness and optical properties of TiO2 thin films was investigated. The films were transparent in the visible wavelength. The thickness of the TiO2 films was increased from 90 nm for the withdraw speed of 1000 μm/s to 160 nm for the withdraw speed of 2000 μm/s. While, The refractive index of the TiO2 thin film decreased from 2.38 to 2.07. It may be due to the porosity of the film was increased. The optical band-gap of the films was around 3.45 eV.

Optical Properties of Sol-Gel (Pb,La)TiO3 Thin Films For Waveguide Application

1995 ◽  
Vol 392 ◽  
Author(s):  
Byeong-Soo Bae ◽  
Won-Jong Lee ◽  
Kwang-Soo No ◽  
Dae-Sung Yoon ◽  
Sung-Uk Kim
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Crystalline Phase ◽  
Sol Gel ◽  
Lanthanum Nitrate ◽  
Processing Conditions ◽  
Heating Condition ◽  
Glass Substrates ◽  
Lanthanum Titanate

AbstractLead lanthanum titanate ((Pb1−x/100Lax)Ti1−x/400O3, x=10, 20, 28) sol-gel thin films were prepared on SiO2/Si and glass substrates using lanthanum nitrate as a La precursor. The effect of the processing conditions was investigated and the optical properties of the films were measured to obtain good films for waveguide applications. The perovskite crystalline phase is achieved regardless of the heating condition but the slower heating creates better quality films. La content in the film does not effect on the refractive index and transparency of the film.

Groove-Free Optical Gratings Self-Assembled by Banana-Shaped Molecules

2010 ◽  
Vol 428-429 ◽  
pp. 272-275
Author(s):  
Yuan Ming Huang ◽  
Qing Lan Ma ◽  
Bao Gai Zhai
Keyword(s):  
Thin Films ◽  
Refractive Index ◽  
Optical Properties ◽  
Self Assembly ◽  
Room Temperature ◽  
Diffraction Gratings ◽  
The Self ◽  
Periodic Modulation ◽  
Glass Substrates ◽  
Alternative Method

. We demonstrate that banana-shaped molecules 1,3-phenylene bis(4-methoxybenzylidene amine) can assemble themselves into diffraction gratings when the melt of the banana-shaped compound, which was sandwiched between two pieces of glass substrates, is cooled to room temperature. Polarizing optical microscopic characterization shows that a pattern of periodic modulation of the refractive index can be developed in the thin films formed by the banana-shaped compound. Despite the gratings are groove free, their optical properties are the same as classically ruled gratings. Our work provides an alternative method for manufacturing diffraction gratings by harnessing the self-assembly of banana-shaped molecules.

scholarly journals Optical properties of metasurfaces infiltrated with liquid crystals

2020 ◽  
Vol 117 (34) ◽  
pp. 20390-20396 ◽  
Author(s):  
Andrew Lininger ◽  
Alexander Y. Zhu ◽  
Joon-Suh Park ◽  
Giovanna Palermo ◽  
Sharmistha Chatterjee ◽  
...  
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Liquid Crystal ◽  
Liquid Crystals ◽  
Optical Design ◽  
Dynamic Control ◽  
Fdtd Simulation ◽  
Optical Elements ◽  
Difference Time ◽  
Local Refractive Index

Optical metasurfaces allow the ability to precisely manipulate the wavefront of light, creating many interesting and exotic optical phenomena. However, they generally lack dynamic control over their optical properties and are limited to passive optical elements. In this work, we report the nontrivial infiltration of nanostructured metalenses with three respective nematic liquid crystals of different refractive index and birefringence. The optical properties of the metalens are evaluated after liquid-crystal infiltration to quantify its effect on the intended optical design. We observe a significant modification of the metalens focus after infiltration for each liquid crystal. These optical changes result from modification of local refractive index surrounding the metalens structure after infiltration. We report qualitative agreement of the optical experiments with finite-difference time-domain solver (FDTD) simulation results. By harnessing the tunability inherent in the orientation dependent refractive index of the infiltrated liquid crystal, the metalens system considered here has the potential to enable dynamic reconfigurability in metasurfaces.

POLYNOMIAL FITTING APPROACH FOR THE KRAMERS–KRONIG METHOD FOR OPTICAL PROPERTIES COMPUTING FOR Bi2O3 FABRIC

2012 ◽  
Vol 26 (07) ◽  
pp. 1250049 ◽  
Author(s):  
GABRIEL MURARIU ◽  
SIMONA CONDURACHE-BOTA ◽  
NICOLAE TIGAU
Keyword(s):  
Experimental Data ◽  
Refractive Index ◽  
Optical Properties ◽  
Reflectance Spectrum ◽  
Optical Parameters ◽  
Thermal Vacuum ◽  
Data Set ◽  
Glass Substrates ◽  
Different Temperatures ◽  
Good Agreement

The optical reflectance of Bi 2 O 3 was measured, and the optical properties were estimated by Kramers–Kronig analysis. The novelty of the present study is due to the implementation of a MAPLE software approach to the complex computations implied by this extrapolation. The analytical fit of the reflectance spectrum is applied, accompanied by a careful extrapolation, which is necessary within the Kramers–Kronig method. In this way starting from the reflectance samples data, using this transformation, a very good agreement is obtained between the main optical parameters, namely the refractive index and the absorbtion coefficient. The study is implemented for Bi 2 O 3 films deposited by thermal vacuum evaporation at different temperatures of the glass substrates and the comparison with the experimental data set being made using the transmission and the reflection optical spectra.

scholarly journals Study the Optical and Spectral Properties of the Acridine Dye As an Effective Medium in Dye Lasers

2018 ◽  
Vol 26 (10) ◽  
pp. 167-180
Author(s):  
Afrah M. AL Hussainey ◽  
Ruaa Kahtan Mahmoud ◽  
Talib M. Abbas ALShafie
Keyword(s):  
Refractive Index ◽  
Optical Properties ◽  
Absorption Coefficient ◽  
Emission Spectrum ◽  
Spectral Properties ◽  
Fluorescence Spectra ◽  
Spectral Characteristics ◽  
Dye Lasers ◽  
Intensity Increase ◽  
Absorption And Fluorescence Spectra

         In this study, the absorption and fluorescence spectra of the dissolved Acridine solution were studied in ethanol and different concentrations. The optical properties (absorption coefficient, linear refraction) and spectral characteristics (Fluorescence time and quantitative fluoridation efficiency) were calculated. It is observed that increasing the concentration increases the absorbance values and decreases the permeability values, thus increasing the values of the absorption coefficient and the refractive index. Also, the values of the fluorine intensity increase. The peak of the emission spectrum is transferred to the longer wavelengths.                                                                                                                    

Preparation and Optical Properties of Gallium-Titanium Codoped Zinc Oxide Transparent Conductive Films for Solar Cells

2013 ◽  
Vol 724-725 ◽  
pp. 176-179
Author(s):  
T. Zhang ◽  
H. Wang ◽  
Z.Y. Zhong ◽  
C.Y. Yang ◽  
Jin Hou
Keyword(s):  
Zinc Oxide ◽  
Refractive Index ◽  
Optical Properties ◽  
Energy Gap ◽  
Oscillator Model ◽  
Optical Energy Gap ◽  
Optical Energy ◽  
Glass Substrates ◽  
Single Oscillator Model ◽  
Single Oscillator

Transparent conducting gallium-titanium codoped zinc oxide thin films were grown onto glass substrates with magnetron sputtering technique in ambient argon gas, and the influence of argon pressure on optical properties of the films were investigated. The refractive indexes of the films were calculated. It is found that the refractive index tends to increase with increasing the photon energy. Meanwhile, the dispersion behavior of the refractive index was analyzed in terms of the single-oscillator model and the oscillator parameters were obtained. Furthermore, the optical energy gaps were evaluated by single-oscillator model and Tauc’s relation, respectively. The values of optical energy gap estimated from single-oscillator model are in agreement with those determined from Tauc’s relation.

A transmission electron microscopic study of structural transitions in fast ionic conductors

1987 ◽  
Vol 45 ◽  
pp. 156-157
Author(s):  
R. B. Queenan ◽  
P. K. Davies
Keyword(s):  
Optical Properties ◽  
Ionic Conduction ◽  
Recent Observation ◽  
Ionic Conductivities ◽  
Sodium Aluminate ◽  
Two Dimensions ◽  
Ionic Conductors ◽  
Electron Microscopic ◽  
Transmission Electron ◽  
Trivalent Cations

Na ß“-alumina (Na1.67Mg67Al10.33O17) is a non-stoichiometric sodium aluminate which exhibits fast ionic conduction of the Na+ ions in two dimensions. The Na+ ions can be exchanged with a variety of mono-, di-, and trivalent cations. The resulting exchanged materials also show high ionic conductivities.Considerable interest in the Na+-Nd3+-ß“-aluminas has been generated as a result of the recent observation of lasing in the pulsed and cw modes. A recent TEM investigation on a 100% exchanged Nd ß“-alumina sample found evidence for the intergrowth of two different structure types. Microdiffraction revealed an ordered phase coexisting with an apparently disordered phase, in which the cations are completely randomized in two dimensions. If an order-disorder transition is present then the cooling rates would be expected to affect the microstructures of these materials which may in turn affect the optical properties. The purpose of this work was to investigate the affect of thermal treatments upon the micro-structural and optical properties of these materials.

Sign in / Sign up

Export Citation Format

Share Document