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1.
本文研究了Zn3BPO7(ZBP)晶体的THz时域光谱以及从中红外到远红外的吸收光谱,以及6.6 cm-1 (0.2 THz)~4000 cm-1宽频段的红外光谱光学性质.THz吸收光谱表明晶体在0.5~1.2 THz有较好的透射性质,在1.7 THz和2.5 THz分别存在一个泛频共振峰和基频共振峰,并且折射率稳定.在远红外区(100~2700 cm-1)晶体的透射率极小,几乎接近于零.在中红外波段(2700~4000 cm-1)晶体具有较好的透射性质.50~4000 cm-1波段的吸收规律表明ZBP晶体具有做成特定波段滤波器的潜力. 相似文献
2.
A. F. Konstantinova V. V. Filippov S. P. Palto E. A. Evdishchenko K. B. Imangazieva V. P. Orekhova 《Crystallography Reports》2007,52(6):1079-1087
The optical properties of a biaxial absorbing KGd(WO4)2:Nd3+ crystal have been investigated. The main refractive indices were measured in the visible spectral range and the absorption and transmission spectra of samples of these crystals were studied. The changes in the refractive indices were in the region of the absorption bands with the use of the Kramers-Kronig relation. Conoscopic pictures of this crystal in the regions of transparency and absorption bands were calculated and are presented. 相似文献
3.
采用真空热蒸发法技术制备CdSe薄膜,通过XRD、SEM、Hall效应和分光光度计测试了薄膜的结构、表面形貌、I-V特性和光学透过率。结果表明:CdSe薄膜(100)晶面的面间距为0.369 nm,晶粒大小约为10.2 nm,薄膜表面晶粒分布较为均匀;CdSe薄膜与锡和银的肖特基势垒高度分别为0.76 V和0.69 V;CdSe薄膜的光透过率在远红外区较高,且呈上升趋势;折射率随波长增加按指数规律减小;根据Tauc关系和Urbach规则,获得能量带隙为1.79 eV和Urbach能量为0.217 eV。 相似文献
4.
A reversible optical transition has been found in thin films of Se---Ge and P---Se---Ge glasses. This optical transition is similar to that found in As---Se---Ge and As---Se---S---Ge glass films; heating causes the shift of the absorption edge to shorter wavelengths, and illumination moves it to longer wavelengths without crystallization. It was found that the presence of arsenic is not always necessary. Fundamental optical properties of these glasses, i.e. absorption constant, optical energy gap, change of the optical energy gap, and the refractive index by heating and illumination are reported. Change of the optical energy gap and the refractive index is small in Se---Ge and P---Se---Ge glasses, compared with that in As---Se---Ge and As---Se---S---Ge glasses. 相似文献
5.
Chalcogenide glasses are interesting materials due to their infrared transmitting properties and photo-induced effects exhibited by them. Thin films of the glasses Sn10Sb20−xBixSe70 (0 x 8) prepared by melt quenching technique were evaporated in a vacuum better than 10−5 mbar. Optical transmission spectra of all the deposited films were obtained in a range 400–2500 nm. The optical band gap and the absorption coefficient were calculated from the transmission data and refractive index was calculated using the swanepoel method. The optical band gap initially increases with increase in Bi content (for x = 2) and then decreases sharply for higher Bi concentrations. The refractive index as well as absorption coefficient decrease with increase in wavelength. The dark activation energy initially increases with increase in Bi content and then decreases with further addition. 相似文献
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7.
《Journal of Non》2006,352(38-39):4076-4081
Glasses in the system Na2O–Al2O3–B2O3–SiO2 doped with MgO, CaO, BaO or ZnO (concentrations: 2.5%–5 mol%) were melted from the raw materials and studied with respect to their densities, hydrolytic durabilities, crystal growth velocities, specific ionic conductivities, refractive indices, Abbe numbers and optical transmissions. The samples were ion exchanged in a NaNO3/AgNO3 salt melt in order to determine the Na+/Ag+ interdiffusion coefficients and the refractive indices, Abbe numbers and optical transmissions of the ion exchanged silver containing glasses. Glasses doped with ZnO are advantageous for the production of gradient index lenses due to their improved chemical durability and smaller crystal growth velocities at viscosities in the range of 105–106 dPa s. The optical properties of these glasses are similar to those of glasses without RO. 相似文献
8.
《Journal of Non》2006,352(32-35):3535-3539
Changes occurring in absorption coefficients when glasses in the SbPO4–WO3 binary system were irradiated by light, at the edge of the absorption band, were measured in real time. These glasses present good thermal and optical properties and photoinduced changes in the absorption coefficients are reversible by heat treatment around 150 °C. Subsequent recording/erasing cycles could be made without sample degradation. The sensitivity of the induced optical changes was studied for different wavelengths, light powers and energy of light dose exposures, and for different compositions of the glasses. The changes in the absorption coefficients of the glass samples were accompanied by a color change from yellow to blue, and were also characterized by visible spectroscopy. The color changes occurred through the entire volume of the glass (∼2 mm thickness) for the Ar-ion laser lines at the edge of the absorption band. 相似文献
9.
《Journal of Non》2007,353(13-15):1350-1353
Effects of CsI content on the optical properties of Ge30Ga5Sb5Se60 glasses were evaluated. Linear and non-linear absorption properties of the glasses without Pr3+ were examined in addition to 1.6 μm emission properties of the Pr-doped glasses. Blueshift of the UV-side absorption edge was accompanied with increasing CsI concentration, while non-linear absorption coefficients measured at 1.06 μm by the Z-scan method remained unaffected. Measured lifetimes of the 1.6 μm emission from modified glasses were comparable to those of the unmodified glass. These experimental observations are discussed in connection with a pronounced weak absorption tail appeared in selenide glasses with the addition of CsI. 相似文献
10.
Yanfei Chen Qiuhua Nie Tiefeng Xu Shixun Dai Xunshi Wang Xiang Shen 《Journal of Non》2008,354(29):3468-3472
A series of bismuth tungsten tellurite glasses were prepared and their densities, linear refractive indices and transmission spectra were measured. The optical bandgaps Eopt and Urbach energies Ee of glasses were obtained from ultraviolet absorption edges. Both the optical gap (Eopt) and the band tail (Ee) are behaving oppositely. As the value of Eopt decreases with increasing WO3 content, the degree of disorder increases which causes more defects or localized states resulting in deep localized in the bandgap with the tailing increased. Z-scan technique was carried out to investigate the third-order nonlinear optical properties of Bi2O3-WO3-TeO2 glasses. The third-order optical nonlinearity increases with decreasing the optical bandgap Eopt, since a increase of WO3 content can provide the non-bridging oxygen ion content. 相似文献
11.
Manabu Ichikawa 《Journal of Non》2010,356(43):2235-2240
We prepared sulfide glasses based on a Ga2S3-GeS2-Sb2S3 system and investigated the compositional dependences of their physico-chemical properties and structure. Additivities were observed for density and refractive index; i.e., these properties were presented by the summation of the contribution from each component. With the increase of Sb2S3 content, the density, refractive index, and thermal expansion coefficient increased while the glass transition and softening temperatures decreased, and the short-wavelength absorption edge shifted to the longer wavelength side. These variations are expected from the incorporation of a heavy element (Sb) into the glasses. On the other hand, the replacement of GeS2 by Ga2S3 increased the density and refractive index, and shifted the short-wavelength absorption edge to the longer wavelength side. These variations were explained by the increase of the number densities of the cations with the replacement and the formation of metal-metal bonds. The latter was confirmed from the Raman spectra. We also investigated the effects of Ag2S incorporation on the optical properties. The incorporation of Ag2S increased the density and refractive index whereas the position of the short-wavelength absorption edge varied little. These results show the possibility of fabricating an optical waveguide by Ag incorporation into the glasses. 相似文献
12.
Tomoharu Hasegawa 《Journal of Non》2011,357(15):2857-4499
Glasses of the Bi2O3-TeO2-B2O3 ternary system were developed and their linear and nonlinear optical properties were investigated. The absorption edges of these glasses were found to be 367-384 nm with a good transmittance in visible wavelength, although they exhibit the refractive indices as high as 1.98-2.12 at 633 nm. The absorption edges are quite steep and they are analyzed by the Urbach theory. The obtained Urbach energies of these glasses are 73-79 meV which are comparable to silica glasses. The high refractive index and its glass composition dependency are discussed according to the basics of the electronic polarizability and optical basicity. The high third order nonlinear susceptibility χ(3) = 2.0 × 10− 12 esu at 800 nm was also obtained in the 36Bi2O3-18TeO2-46B2O3 glass. 相似文献
13.
M. Guignard V. Nazabal A. Moreac S. Cherukulappurath G. Boudebs H. Zeghlache G. Martinelli Y. Quiquempois F. Smektala J.-L. Adam 《Journal of Non》2008,354(12-13):1322-1326
New class of chalcohalide glasses has been prepared in the GeS2–In2S3–CsI system with regard to their potential non-linear properties. The study of glass-forming region was undertaken to select glassy compositions, which present high non-linear (NL) optical properties with a low two-photon absorption. Thermal analyses, structural examination by Raman spectroscopy, non-linear optical measurements were investigated as a function of CsI contents. Introduction of CsI has shifted the band-gap edge towards the blue region of the absorption optical spectrum and therefore has limited the two-photon absorption. Their NL refractive index n2 are 60 times higher than silica glasses without any NL absorption. Moreover, second harmonic signal was observed in thermally poled samples similar to silica glass. However, this second order non-linearity is not temporally stable. 相似文献
14.
Robert D. Maurer 《Journal of Non》1982,47(1):135-146
The advances in optical waveguides have permitted a clear measurement of many glass properties normally obscured by impurities in conventional glasses. Among these is the intrinsic optical absorption in both the infrared and ultraviolet regions. The wavelength dependence and the statistical fluctuations of another intrinsic property, the refractive index, have also been determined in detail. Knowing accurately the foregoing characteristics of “pure” glasses, deviations due to additives are easier to detect. This has led to absorption determinations for atomic defects and selected impurities as well as for deliberate additions of other oxides. 相似文献
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Yusuke Hashimoto Tatsuya Mori Seiji Kojima 《Molecular Crystals and Liquid Crystals》2016,629(1):258-263
The low-energy vibrational properties of polymethyl methacrylate (PMMA) were studied by terahertz time-domain spectroscopy and Raman scattering. The real and imaginary parts of a complex dielectric constant were accurately determined in the frequency range from 0.2 to 5.0 THz. The imaginary part of the dielectric constant shows a line-shape similar to the imaginary part of the Raman susceptibility measured by Raman scattering. These two spectra show broad peaks at about 2.3 THz. We also separately determined the Raman and far-infrared light-vibration coupling constants of the PMMA using the vibrational density of states determined by cold neutron inelastic scattering in the literature. 相似文献
17.
P. Becker 《Crystal Research and Technology》2003,38(1):74-82
In the binary system Bi2O3 – B2O3 glasses were prepared in the composition range 57.5 mol% ‐ 80 mol% B2O3 by defined slow cooling of large melt samples (about 75 cm3, each). Temperatures of crystallization, of melting and of glass transition were determined and density data of the glasses were derived using the hydrostatic weighting method. Thermal expansion coefficients and high precision refractive indices, together with their dispersion, were measured. The measured physical properties indicate subtle discontinuous structural changes of the glasses with glass composition, that match with the ranges of existence of the crystalline compounds of the binary system Bi2O3 – B2O3. Thermal investigations together with X‐ray powder diffraction analyses of crystallized glass samples prove the so far doubtful existence of a borate compound named “BiBO3” in the PDF within the composition range 52.5 – 57.5 mol% B2O3. 相似文献
18.
Cerium oxide is commonly added to silicate glasses as an optical property modifier. In particular, UV absorption, decoloration via redox coupling, and resistance to radiation-induced darkening are influenced by the addition of this rare-earth oxide. However, the limited solubility and visible color of rare-earth oxides in silicate glasses prevent any further beneficial enhancement of properties which might result from increasing the CeO2 content. In contrast, rare-earth oxides are extremely soluble in phosphate glasses; for example, a binary cerium phosphate glass can incorporate up to 40 mol% CeO2. Moreover, since the UV absorption edge of the phosphate network is blue-shifted compared to the silicate network, the effect of the Ce3+ absorption band tail on yellow coloration can be minimized.In this study, glasses in the cerium aluminosilicophosphate system were synthesized and a variety of physical and optical properties were measured including: density, refractive index, glass transition temperature, hardness, fracture toughness, and the location of the UV absorption edge. At ~9 mol% CeO2, these cerium aluminosilicophosphate glasses exhibit similar coloration to commercially available silicate glasses which contain ~0.4 mol% CeO2. Semi-quantitative photoemission analysis of the Ce oxidation states showed insignificant differences in the Ce3+/Ce4+ ratio between the phosphate and silicate glass systems. 相似文献
19.
Transparent glasses containing copper nanoparticles are promising materials for ultrafast all-optical switches in the THz region due to their wide range of resonant absorption frequencies, ultrafast time response, as well as large third-order nonlinear optical coefficients associated with the surface plasmon resonance (SPR) in the visible region. In this paper, three dimension controllable precipitation of copper nanoparticles inside a borosilicate glass by irradiation of femtosecond laser pulses is studied. According to the designed program, different patterns made up of copper nanoparticles can be induced inside the glass sample. Absorption spectra are used to confirm the precipitation of copper nanoparticles. The precipitated nanoparticles can be space-selectively “dissolved” by the second time femtosecond laser irradiation. The involved mechanisms are discussed. 相似文献
20.
《Journal of Non》2007,353(16-17):1618-1623
Amorphous thin films from the As2Se3–Ag4SSe–SnTe system were prepared by thermal vacuum evaporation from the corresponding bulk glasses. Their transmission, reflection, scattering and ellipsometric spectra were measured in the UV, VIS and NIR regions, and the results were mathematically simulated using the Tauc–Lorentz dispersion model in order to obtain the refractive index and extinction coefficient. The compositional dependence of the derived optical properties was found and discussed. 相似文献