scholarly journals Compositional dependence of optical band gap and refractive index in lead and bismuth borate glasses

2015 ◽  
Vol 68 ◽  
pp. 27-34 ◽  
Author(s):  
Saisudha B. Mallur ◽  
Tyler Czarnecki ◽  
Ashish Adhikari ◽  
Panakkattu K. Babu
2013 ◽  
Vol 770 ◽  
pp. 153-156
Author(s):  
Onanong Chamlek ◽  
Pruittipol Limkitjaroenporn ◽  
Hong Joo Kim ◽  
Jakrapong Kaewkhao

Neonymium doped bismuth borate glasses with composition 50Bi2O3 : (50-x)B2O3: xNd2O3 (where x = 0.5, 1.0, 1.5, 2.0 and 2.5 mol%) have been prepared by melt quenching technique. The optical and upconversion luminescence properties of glasses were investigated. The nine absorption peaks were observed, correspond with Nd3+ energy level in glass. The optical band gap decreased with increasing Nd2O3 concentration due to the increase of non-bridging oxygen (NBOs) in glass matrix. The upconversion luminescence emission spectra shows peak at 393 nm, assign to 4D3/24I11/2 transition.


2016 ◽  
Vol 675-676 ◽  
pp. 347-350
Author(s):  
Sopanat Kongsriprapan ◽  
Kanyakorn Teanchai ◽  
Keerati Kirdsiri ◽  
Jakrapong Kaewkhao ◽  
Wichian Siriprom

The glass samples in bismuth borate glass matrix containing Al2O3, with the composition of xAl2O3 : 30Bi2O3 : (70-x)B2O3 where x are Al2O3 concentration varying from 0.0, 2.0, 4.0, 6.0, 8.0 and 10.0 mol%, have been prepared. The obtained glasses were investigated some physical and optical properties. The results showed that the densities increased with increasing of Al2O3 concentration, whereas the molar volumes decreased. For the absorption spectra, no peak in the UV to NIR regions has been observed. Moreover the energy band gap and the refractive index for all samples have been calculated.


2013 ◽  
Vol 770 ◽  
pp. 72-75 ◽  
Author(s):  
Keerati Kirdsiri ◽  
Nattapon Srisittipokakun ◽  
Yotsakit Ruangtaweep ◽  
Kitipun Boonin ◽  
Pichet Limsuwan ◽  
...  

Bismuth titanium borate glasses in compositions xTiO2 : (30-x)Bi2O3 : 70B2O3 (with x is in mol%, varying from 0% to 10%) were fabricated by the conventional melt quenching technique. The effect of TiO2 on the physical and spectroscopic properties of bismuth borate glasses have been carried out by means of density and UV-Visible spectroscopy measurement techniques. The density and molar volume of all glasses are found to change depend on TiO2 substitution. The fundamental absorption edges for all glasses have been identified using the theory proposed by Davis and Mott. The optical band gap (Eg) is found to decrease with increase in TiO2 content.


Polymers ◽  
2021 ◽  
Vol 13 (8) ◽  
pp. 1316
Author(s):  
Shujahadeen B. Aziz ◽  
Muaffaq M. Nofal ◽  
Hewa O. Ghareeb ◽  
Elham M. A. Dannoun ◽  
Sarkawt A. Hussen ◽  
...  

The influence of dispersing Al-metal complex on the optical properties of PVA was investigated using UV–visible spectroscopy. Polymer composite films with various Al3+-complex amounts in the PVA matrix were arranged by solution casting technique by means of distilled water as a widespread solvent. The formation of Al3+-metal complex was verified through Ultraviolet–visible (UV-Vis) and Fourier-transform infrared spectroscopy (FTIR) examinations. The addition of Al-complex into the polymer matrix led to the recovery of the optical parameters such as dielectric constant (εr and εi) and refractive index (n). The variations of real and imaginary parts of complex dielectric constant as a function of photon wavelength were studied to calculate localized charge density values (N/m*), high-frequency dielectric constant, relaxation time, optical mobility, optical resistivity, and plasma angular frequency (ωp) of electrons. In proportion with Al3+-complex content, the N/m* values were amplified from 3.68 × 1055 kg−1 m−3 to 109 × 1055 kg−1 m−3. The study of optical parameters may find applications within optical instrument manufacturing. The optical band gap was determined from Tauc’s equation, and the type of electronic transition was specified. A remarkable drop in the optical band gap was observed. The dispersion of static refractive index (no) of the prepared composites was analyzed using the theoretical Wemple–DiDomenico single oscillator model. The average oscillator energy (Eo) and oscillator dispersion energy (Ed) parameters were estimated.


2021 ◽  
Vol 317 ◽  
pp. 95-99
Author(s):  
Muhammad Noorazlan Abd Azis ◽  
Halimah Mohamed Kamari ◽  
Suriani Abu Bakar ◽  
Azlina Yahya ◽  
Umar Saad Aliyu

Borotellurite glass had been widely applied in the field of optical communications and devices. In this work, holmium oxides doped borotellurite glass had been successfully fabricated via conventional melt-quenched technique. The structural properties of holmium doped tellurite glass were found using x-ray diffraction (XRD) method. The nonexistence of sharp peaks in XRD pattern shows that the inclusion of holmium tellurite glass leads to the formation long range of disorderness. The optical properties of the glass system such as refractive index and optical band gap energy are investigated using UV-Vis spectrophotometer. The value of refractive index is found in nonlinear trend along with holmium oxides concentration. It is found that the refractive index is more than 2 at 0.01, 0.03 and 0.04 of holmium concentrations. The optical band gap energy was found in similar trend with refractive index which is in nonlinear pattern.


2013 ◽  
Vol 37 (1) ◽  
pp. 83-91 ◽  
Author(s):  
Chitra Das ◽  
Jahanara Begum ◽  
Tahmina Begum ◽  
Shamima Choudhury

Effect of thickness on the optical and electrical properties of gallium arsenide (GaAs) thin films were studied. The films of different thicknesses were prepared by vacuum evaporation method (~10-4 Pa) on glass substrates at a substrate temperature of 323 K. The film thickness was measured in situ by a frequency shift of quartz crystal. The thicknesses were 250, 300 and 500 nm. Absorption spectrum of this thin film had been recorded using UV-VIS-NIR spectrophotometer in the photon wavelength range of 300 - 2500 nm. The values of some important optical parameters of the studied films (absorption coefficient, optical band gap energy and refractive index; extinction co-efficient and real and imaginary parts of dielectric constant) were determined using these spectra. Transmittance peak was observed in the visible region of the solar spectrum. Here transmittance showed better result when thicknesses were being increased. The optical band gap energy was decreased by the increase of thickness. The refractive index increased by increasing thickness while extinction co-efficient and real and imaginary part of dielectric constant decreased. DOI: http://dx.doi.org/10.3329/jbas.v37i1.15684 Journal of Bangladesh Academy of Sciences, Vol. 37, No. 1, 83-91, 2013


2012 ◽  
Vol 710 ◽  
pp. 739-744 ◽  
Author(s):  
Anup Kumar ◽  
Pawan Heera ◽  
P. B Baraman ◽  
Raman Sharma

The optical constants, like absorption coefficient (α), optical band gap (Eg) and refractive index (n), in Se80.5Bi1.5Te18-yAgy (y= 0, 1.0 and1.5) thin films are calculated using well known Swanepoel’s method in the spectral range of 600-2000 nm. The optical band gap has been estimated by using Tauc’s extrapolation method and is found to increase with increase in Ag content. The present results shows that the large value of nonlinear refractive index and good transparency of these thin films will make them a very promising materials for optical integrated circuits in the optical communication systems.


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