-
[show abstract]
[hide abstract]
ABSTRACT: To assess the effect of sulfur dioxide impurity on the optical properties and absorption spectrum of glassy arsenic sulfide,
we have prepared As2S3 glass samples containing 0.01 to 0.12 wt % SO2 and have measured their transmission spectra in the range 500–5000 cm−1. The extinction coefficient of sulfur dioxide in glassy arsenic sulfide, evaluated from the intensity of the 1158-cm−1 absorption band, is 10.0 ± 0.7 cm−1/wt%.
Inorganic Materials 05/2012; 42(12):1388-1392. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: We report a computer simulation study of the diameter uniformity of optical fibers produced by drawing through a nozzle. We
determine the natural frequency and decrement of melt flow rate oscillations downstream of the nozzle and examine the effect
of temperature ripple on deviations of the fiber diameter from its nominal value. It is shown that cooling the melt jet stabilizes
the melt flow and the fiber diameter.
Inorganic Materials 05/2012; 46(3):304-309. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The data on the present degree of purity of chalcogenide glasses for fiber optics, on their methods of production and on the
properties, which are essential for their actual application, are generalized. The content of limiting impurities in the best
samples of chalcogenide glasses is 10–100 ppb wt.; of heterophase inclusions with size of about 100 nm is less than 103 cm−3. On the basis of chalcogenide glasses the multimode and single mode optical fibers are produced with technical and operation
characteristics sufficient for a number of actual applications. The minimum optical losses of 12–14 dB/km at 3–5 µm are attained
in the optical fiber from arsenic-sulfide glass. The level of losses in standard chalcogenide optical fibers is 50–300 dB/km
in 2–9 µm spectral range. The factors, affecting the optical absorption of glasses and optical fibers, are analyzed, and the
main directions in further development of chalcogenide glasses as the materials for fiber optics are considered.
Inorganic Materials 04/2012; 45(13):1439-1460. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Absorption spectra of Ni$^{2+}$ ions in 22WO$_3$--78TeO$_2$
tungstate-tellurite glass were studied and Ni$^{2+}$ extinction coefficient
spectral dependence was derived in the 450 -- 2700 nm wavelength range.
Computer modeling of the glass structure proved Ni$^{2+}$ ions to be in
trigonal-distorted octahedral environment in the tungstate-tellurite glass.
Tanabe-Sugano diagram for such an environment was calculated and good
description of the observed spectrum of Ni$^{2+}$ ion was obtained. Basing on
both absorption spectral range width and the extinction coefficient, nickel
should be considered among the most strongly absorbing impurities in the
tellurite glasses.
01/2011;
-
[show abstract]
[hide abstract]
ABSTRACT: The threshold intensities of the radiation required for sustaining the optical discharge waves in various silica fibres for different wavelengths of laser radiation are measured. It is shown that over a wide range of experimental conditions, the threshold intensity is determined mainly by the diameter of the mode field in the fibre. The destruction of chalcogenide and fluoride fibres upon exposure to laser radiation of power ~ 1 W is studied for the first time. The optical discharge wave is not formed in such fibres, and the destruction occurs due to thermal decomposition of the fibre material over the entire cross section of the fibre. The destruction of these fibres is characterised by much lower threshold intensities of laser radiation than in the case of silica fibres.
Quantum Electronics 10/2007; 32(6):476. · 0.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The damage thresholds of bulk high-purity chalcogenide glass samples and of fibre waveguides made from them were determined for YAG : Er laser radiation (λ = 2.94 μm). A cumulative effect was observed: the optical strength decreased during repetitive application of laser pulses and this was true both of the bulk samples and of the fibre waveguides. A correlation between the damage threshold and the concentration of heterophase inclusions was established experimentally. When the inclusion concentration was less than 104 cm-3, the damage threshold exceeded 1 kJ cm-2 for single pulses and was approximately half that in the pulse-periodic regime. The measured energy density of the λ = 2.94 μm radiation, needed for efficient cutting of the crystalline lens biotissues in the human eye, amounted to 50 J cm-2. The feasibility of constructing a scalpel with an Er laser and transmission of its high-power radiation (up to 1 kJ cm-2) along a chalcogenide fibre waveguide was demonstrated in principle.
Quantum Electronics 10/2007; 25(5):498. · 0.83 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Using a flow method, we have measured the vapor pressure of tellurium tetraiodide, an attractive reagent for chemical vapor
deposition technology. The results, combined with earlier tensimetric data, have been used to evaluate the basic thermodynamic
functions of TeI4 and its thermolysis products.
Inorganic Materials 01/2007; 43(9):1018-1023. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Single-mode As–S glass fibers with a core diameter from 3 to 20 m and a clad diameter of 125 m are prepared by the double-crucible method. The cutoff wavelength of the fibers is 0.9–6 m. The lowest transmission losses in the fibers at 2.2–2.3 m are 100 dB/km, and their mean bending strength is 800–1000 MPa.
Inorganic Materials 05/2003; 39(6):627-630. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The variations in the optical losses and bending strength of high-purity As–S, As–Se, As–S–Se, and As–Se–Te glass fibers during storage in air were studied. The optical properties and strength of fibers with reflecting clads and well-protected surfaces were shown to be sufficiently stable for practical applications. The optical and mechanical properties of uncoated fibers degrade during storage because of adverse surface processes.
Inorganic Materials 09/2002; 38(10):1063-1068. · 0.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Catastrophic destruction of fluoride and chalcogenide optical
fibres under laser radiation in the wavelength region 1-1.5 μm has
been investigated for the first time. Different characteristics and much
lower thresholds of catastrophic damage compared to silica-based fibres
have been discovered
Electronics Letters 08/2002; · 0.96 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: Optical and mechanical characteristics of optical fibers made of high-purity chalcogenide glasses of As-S, As-S-Se, As-Se and Ge-As-Se systems, intended for operation in the middle IR, are given. The fibers from As-S glass will be useful for transmission of IR-radiation in the 1-7 microns spectral region, the fibers on the basis of As-Se and Ge-As-Se glass systems - in the 2-12 microns region. The multimode fibers from arsenic-sulfide and arsenic-selenide glasses have the minimum optical losses equal to 23 +/-8 dB/km and 79 +/-10dB/km at 2.4 and 4.5 microns, respectively.
05/2001;
-
[show abstract]
[hide abstract]
ABSTRACT: Low impurity content is the essential requirement to many applications of vitreous arsenic chalcogenides as a material for optoelectronics. Investigations carried out in last ten years increased the knowledge volume about the nature and origin of impurities in chalcogenide glasses, their effect on glass properties, especially on the transmittance in middle IR region and on radiation strength. These properties are most sensitive to impurity presence. The minimum calculated content of impurities, leading to observation of impurity contribution to the property value, is 0.1 - 100 ppb at. for different impurity groups. The effective methods of preparations and analysis of high purity glasses are developed.
05/2001;
-
[show abstract]
[hide abstract]
ABSTRACT: A 3-mum laser-generation delivery instrument that uses chalcogenide fibers with a unique damage threshold and conical radiation input has been developed for medical applications. A new purification and synthesis scheme has been elaborated that yields fibers with a heterophase inclusion content of less than 10(4) cm(-3). In such fibers the damage threshold is 350 J/cm(2) at an average power density of 0.5 kW/cm(2) in a YAG:Er laser operating in the repetitive pulse free-running regime with a pulse duration of 350 ms. 1-3 x 10(4) laser pulses were transmitted at a repetition rate of 3 Hz and an average output power of 1 W under the condition of a 15% decrease in the output power.
Applied Optics 09/1998; 37(24):5596-9. · 1.41 Impact Factor
-
[show abstract]
[hide abstract]
ABSTRACT: The processes of production of high-purity glasses based on arsenic chalcogenides and optical fibers with low optical losses in the middle IR have been analyzed. Physical–chemical, technological and methodological factors determining the degree of purity of glasses and the level of optical losses in optical fibers are considered. Dominant factors, rational actions and approaches optimizing the manifestation of these factors in glasses formed by arsenic chalcogenides are discussed. Vitreous As2S3 is produced with the content of hydroxyl groups not more than 1 ppb wt, of hydrogen in the form of SH-groups — 75 ppb mol, of silicon — 0.2 ppm wt. From this glass a multi-mode optical fiber was manufactured with optical losses of 12 and 14 dB/km at 3.0 and 4.8 μm, respectively, which is the best result published in literature for chalcogenide glass optical fibers.
Journal of Non-Crystalline Solids 357:2352-2357. · 1.54 Impact Factor
