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Glasses
Published in Marvin J. Weber, and TECHNOLOGY, 2020
Chalcogenide glass fibers are normally used as infrared transmitting “lightpipes” rather than data transmission links. Depending on composition, their optical window can extend from the visible, deep into the IR (see Figure 18.2.22).71,72 Applications for the fibers include infrared imaging, pyrometry, chemical sensing, and laser power delivery.73–75 Sulfide fibers are appropriate for Er:YAG (2.9 μm) and CO (5.5 μm) lasers but heavier chalco- genides are required for CO2 (10.6 μm) laser power. Losses below 1 dB/m are often targeted as a practical limit for power delivery. No chalcogenide fibers have yet met this target, under ambient conditions, at the CO2 laser wavelength. Weak absorption effects76,77make these fibers improbable candidates for ultralow-loss communication links.
Wavelength Conversion
Published in Mário F. S. Ferreira, Optical Signal Processing in Highly Nonlinear Fibers, 2020
Since silica glass presents too much loss beyond 2 µm, novel highly nonlinear materials, with high transparency over a broad wavelength range, have to be considered for operation of chalcogenide glass in the SWIR and MIR wavelength ranges. An approach relies on using microstructured fibers made of chalcogenide glass. This glass has a third-order nonlinearity up to 1000 times that of silica, as well as a broad transparency window up to 10 µm or 15 µm in the MIR, depending on the glass composition. In addition, as seen in Chapter 3, microstructured optical fibers offer great design flexibility. By controlling the structural parameters of a microstructured optical fiber (MOF), we can adjust its dispersion characteristics, which becomes especially important in the case of the FWM process. In a 2016 experiment, wavelength conversion in the 2 µm region by FWM in an AsSe and a GeAsSe chalcogenide MOF has been demonstrated [37]. A conversion efficiency of −25.4 dB was measured for 112 mW of coupled continuous wave pump in a 27-cm-long fiber.
Physical Properties of Glass Infrared Optical Materials
Published in Paul Klocek, Handbook of Infrared Optical Materials, 2017
James Steve Browder, Stanley S. Ballard, Paul Klocek
Notes: Ge25Se75 chalcogenide glass is of interest for infrared optical components because of its transparency in the 8–12-µm region and its relatively good thermal, mechanical, and chemical properties. Germanium-selenium glass of various compositions with a range of similar physical properties have been made.
Thermal stability and crystallization kinetics of Ge13In8Se79 chalcogenide glass
Published in Phase Transitions, 2019
Gh. Abbady, Alaa M. Abd-Elnaiem
The crystallization kinetics and the physical properties of glasses may be affected by the presence of nano- or microcrystallites inclusions through the glass formation. Generally, chemical interaction of chalcogenide and some impurities with silica glass container or apparatus material at elevated temperatures leads to thin layer formation of new compounds on the inner surface of a container, and to the appearance of heterogeneous inclusions in chalcogenide melt. The formation of chalcogenide glasses free of impurities and inclusion requires some important steps and methods. The glasses contained inclusions of hetero-phase impurity and their concentration and size depending on the conditions of glass preparation. For example, the size/concentration of inclusion decreases/increases with increasing the preparation temperature. In addition, the preparation under high vacuum could reduce the concentration of these inclusions. The investigation of the existence of inclusions can be carried out using laser ultramicroscopy. Heterophase inclusions lead to optical losses in chalcogenide glass due to absorption and scattering. Further study is in progress to investigate the existence and behaviors of such inclusion in the studied glass.
Study of the electrical and optical properties of Ge27Se58Pb15 chalcogenide glass
Published in Journal of Asian Ceramic Societies, 2018
Hukum Singh, K. S. Rathore, N. S. Saxena
Chalcogenide glasses are interesting materials due to their transparency in visible or near infrared region up to 15 μm and their good stability for outdoor applications. At this wavelength, thermal imaging is done using exclusively single crystalline germanium, which is rare and expensive element. Chalcogenide glasses have taken the place of germanium in thermal imaging due to its low cost and possibility of obtaining glass fibers by molding due to its vitreous nature. Now days, chalcogenide glass lenses are widely used in infrared cameras and the optical performance of the system is the same as obtained using germanium [1–3]. Chalcogenide glasses based on Ge–Se are widely used for optical fibers for light transmission especially when short length and flexibility is required [4–10]. The structure of Ge–Se is basically comprised of Ge with coordination four and Se atoms with coordination two. When 33% of Ge is added to Se, chains or rings of Se are bridged by the tetrahedral bonds of Ge forming basic structural unit of Ge–Se system [9].
Investigation of the gamma photon shielding in Se–Te–Ag chalcogenide glasses using the Phy-X/PSD software
Published in Cogent Engineering, 2022
Fatemah. H. Alkallas, Amira Ben Gouider Trabelsi, Samira Elaissi, Tahani A. Alrebdi, Lamia Abu El Maati, Fatma. B. M. Ahmed, M. M. Mahasen, M. Ahmad, M. M. Soraya
Recently, glasses have attracted considerable attention for use in shielding products attributed to their remarkable characteristics for radiation shielding, such as transparency, good thermal stability, and fabrication flexibility in various sizes and shapes as reported by Yankov et al. (2012) and Guo et al. (2016). The chalcogen elements S, Se, and Te provide the basis for the versatile materials known as chalcogenide glasses. These glasses are utilized in a variety of technological applications as introduced by Schindler et al. (2009), Hewak (2011), Ailavajhala et al. (2014), and Donghui et al. (2006). There is great interest toward chalcogenide glass-ceramics in the field of radiation shielding because of their promising physical, optical, and thermal properties. Also, they are very sensitive to irradiations because of their flexible structures as given by Mikla et al. (2018). Chalcogenide glasses were investigated by many researchers for shielding applications. Te-based glasses exhibit high thermal stability and fast crystallization times, which makes it applicable in many different applications as presented by Mhareb et al. (2021). Al-Buriahi and Mann (2019) investigated the radiation-shielding capabilities of Te, Nb, and W glass composite. Alzahrani et al. (2021) studied the radiation protection of a TeO2-Na2O-TiO glasses. Both investigations showed the importance of Te element for radiation shielding in the investigated glass systems. Amorphous Se–Te glasses show high photosensitivity and high hardness. Ag-doped chalcogenide glasses attract many researchers for fundamental research in many applications including radiation shielding. Ge-Se-Sb-Ag composites were investigated by Kebaili et al. (2021) for the radiation shielding ability. They show that the Ge-Se-Sb-Ag glasses exhibit good ability to gamma-ray and also beta -ray shielding. Shielding properties for (GeS2)60-(Sb2S3)40-x-(CdCl2)x (0 ≤ x ≤ 40 mole %) chalcogenide glasses were examined by El-Agawany et al. (2020). These glasses showed good protection properties against gamma rays and neutrons. In this research Se–Te–Ag chalcogenide glass with a new composite was chosen for further investigation concerning shielding properties. This can help to can adopt the best compositions for such materials in shielding applications.