Temperature dependence of the optical properties of Bi2O3. A theoretical approach basing on the Kramers-Kronig transformation for polynomial mixed terms models

Open Physics ◽  
2013 ◽  
Vol 11 (1) ◽  
Author(s):  
Gabriel Murariu ◽  
Simona Condurache-Bota

AbstractThe Kramers-Kronig transforms (KK) constitute a powerful tool to validate experimental data. The present study is implemented for Bi2O3 thin films deposited by thermal vacuum evaporation at different temperatures of the glass substrates. Since the extraordinary properties of this fabric allow us to consider particular analytical approach as it was previously shown, the reflectance properties of Bi2O3 as a function of temperature could be studied.The novelty of this article is the studying of a global effective analytical representation, based on polynomial functions, in order to obtain a general model that includes temperature dependence of the optical properties, using the Kramers-Kronig transformation type. In the mathematical expressions, were included mix combined term in order to avoid the effects of Runge phenomenon. As a case study was chosen Bi2O3 — a substance less studied in literature. In the last part are the presented and commented the results obtained for a series of eight studied models.

2012 ◽  
Vol 26 (07) ◽  
pp. 1250049 ◽  
Author(s):  
GABRIEL MURARIU ◽  
SIMONA CONDURACHE-BOTA ◽  
NICOLAE TIGAU

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.


2011 ◽  
Vol 130-134 ◽  
pp. 1379-1382
Author(s):  
Rui Fang Chen ◽  
Jie Yu ◽  
Yin Qun Hua ◽  
Rui Li Xu ◽  
Hai Xia Liu

Nanocrystalline ZnS thin films were deposited on glass substrates at 300W and 0.6Pa by using radio frequency magnetron sputtering, and then annealed at different temperatures. This work investigated the influence of ZnS buffer layer on different annealing temperature, analysed structural, surface topography, and optical properties of ZnS films by using X-ray diffraction (XRD), UV-spectroscopy measurements and scanning electronic microscope (SEM) analysis techniques. Findings showed that the film annealed at 300°C was uniformity and compact, which was zinc blende cubic structure. The film exhibited the optical transparency as high as 85% in the visible region, and its optical band gap was calculated to be 3.56 eV.


Author(s):  
Atefeh Nazari Setayesh ◽  
Hassan Sedghi

Background: In this work, CdS thin films were synthesized by sol-gel method (spin coating technique) on glass substrates to investigate the optical behavior of the film. Methods: Different substrate spin coating speeds of 2400, 3000, 3600 rpm and different Ni dopant concentrations of 0 wt.%, 2.5 wt.%, 5 wt.%) were investigated. The optical properties of thin films such as refraction index, extinction coefficient, dielectric constant and optical band gap energy of the layers were discussed using spectroscopic ellipsometry method in the wavelength range of 300 to 900 nm. Results: It can be deduced that substrate rotation speed and dopant concentration has influenced the optical properties of thin films. By decreasing rotation speed of the substrate which results in films with more thicknesses, more optical interferences were appeared in the results. Conclusion: The samples doped with Ni comparing to pure ones have had more optical band gap energy.


Author(s):  
Minakshi Chaudhary ◽  
Yogesh Hase ◽  
Ashwini Punde ◽  
Pratibha Shinde ◽  
Ashish Waghmare ◽  
...  

: Thin films of PbS were prepared onto glass substrates by using a simple and cost effective CBD method. Influence of deposition time on structural, morphology and optical properties have been investigated systematically. The XRD analysis revealed that PbS films are polycrystalline with preferred orientation in (200) direction. Enhancement in crystallinity and PbS crystallite size has been observed with increase in deposition time. Formation of single phase PbS thin films has been further confirmed by Raman spectroscopy. The surface morphology analysis revealed the formation of prismatic and pebble-like PbS particles and with increase in deposition time these PbS particles are separated from each other without secondary growth. The data obtained from the EDX spectra shows the formation of high-quality but slightly sulfur rich PbS thin films over the entire range of deposition time studied. All films show increase in absorption with increase in deposition time and a strong absorption in the visible and sub-band gap regime of NIR range of the spectrum with red shift in band edge. The optical band gap shows decreasing trend, as deposition time increases but it is higher than the band gap of bulk PbS.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Chuan Lung Chuang ◽  
Ming Wei Chang ◽  
Nien Po Chen ◽  
Chung Chiang Pan ◽  
Chung Ping Liu

Indium tin oxide (ITO) thin films were grown on glass substrates by direct current (DC) reactive magnetron sputtering at room temperature. Annealing at the optimal temperature can considerably improve the composition, structure, optical properties, and electrical properties of the ITO film. An ITO sample with a favorable crystalline structure was obtained by annealing in fixed oxygen/argon ratio of 0.03 at 400°C for 30 min. The carrier concentration, mobility, resistivity, band gap, transmission in the visible-light region, and transmission in the near-IR regions of the ITO sample were-1.6E+20 cm−3,2.7E+01 cm2/Vs,1.4E-03 Ohm-cm, 3.2 eV, 89.1%, and 94.7%, respectively. Thus, annealing improved the average transmissions (400–1200 nm) of the ITO film by 16.36%. Moreover, annealing a copper-indium-gallium-diselenide (CIGS) solar cell at 400°C for 30 min in air improved its efficiency by 18.75%. The characteristics of annealing ITO films importantly affect the structural, morphological, electrical, and optical properties of ITO films that are used in solar cells.


1990 ◽  
Vol 201 ◽  
Author(s):  
Honglie Shen ◽  
Genqing Yang ◽  
Zuyao Zhou ◽  
Guanqun Xia ◽  
Shichang Zou

AbstractDual implantations of Si+ and P+ into InP:Fe were performed both at 200°C and room temperature. Si+ ions were implanted by 150keV with doses ranging from 5×1013 /cm2 to 1×1015 /cm2, while P+ ions were implanted by 110keV. 160keV and 180keV with doses ranging from 1×l013 /cm2 to 1×1015 /cm2. Hall measurements and photoluminescence spectra were used to characterize the silicon nitride encapsulated annealed samples. It was found that enhanced activation can be obtained by Si+ and P+ dual implantations. The optimal condition for dual implantations is that the atomic distribution of implanted P overlaps that of implanted si with the same implant dose. For a dose of 5×l014 /cm2, the highest activation for dual implants is 70% while the activation for single implant is 40% after annealing at 750°C for 15 minutes. PL spectrum measurement was carried out at temperatures from 11K to 100K. A broad band at about 1.26eV was found in Si+ implanted samples, of which the intensity increased with increasing of the Si dose and decreased with increasing of the co-implant P+ dose. The temperature dependence of the broad band showed that it is a complex (Vp-Sip) related band. All these results indicate that silicon is an amphoteric species in InP.


1993 ◽  
Vol 316 ◽  
Author(s):  
Yukinori Saito ◽  
Shinji Suganomata ◽  
P. Moretti

The optical properties of colorless and transparent crystals can be changed by introducing impurities into the crystal and depend on the elements added. What kind of elements should be added depends on how one modifies the properties. If one wants to put beautiful color on some colorless and transparent crystals such as Al203, SiO2, LiNbO3, etc., it is necessary to produce definite absorption peaks in the visible region for the crystals. In case of using ion implantation for introducing impurities, there is essentially no limitation to the combination of host crystal and impurities.


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