Search results for "Chalcogenide Glass"
showing 10 items of 21 documents
Chalcogenide Microstructured Fibers for Infrared Systems, Elaboration, Modelization, and Characterization
2009
special issue " Fiber Optic Research in France " (Part III of III); International audience; Chalcogenide fibers present numerous possible applications in the IR field. For many applications, single mode fibers must be obtained. An original way is the realization of microstructured optical fibers (MOFs) with solid core. These fibers present a broad range of optical properties thanks to the high number of freedom degrees of their geometrical structure. In this context, we have developed MOFs for near and mid IR transmission with different geometries and properties such as multimode or endless single-mode operation, small or large mode area fibers. We have also investigated numerically the mai…
Theoretical study of cascade laser in erbium-doped chalcogenide glass fibers
2010
International audience; A theoretical investigation of an innovative cascade laser source is performed. The main goal of the work is the design of a continuous-wave (CW) photonic crystal fiber (PCF) laser, based on an erbium-doped chalcogenide glass. Due to the comparable lifetimes of the 4I13/2, 4I11/2 and 4I9/2 erbium energy levels, the simultaneous emissions at the wavelengths close to 2.7 μm and 4.5 μm are obtained with a pump wavelength close to 806 nm (direct pumping into the level 4I9/2). This scheme could be useful to develop high efficiency, high beam-quality and compact Near-IR and Mid-IR oscillators with single-mode output for applications not only in surgery but also in spectros…
Experimental investigation of Brillouin and Raman scattering in a 2SG sulfide glass microstructured chalcogenide fiber.
2008
International audience; In this work, we investigate the Brillouin and Raman scattering properties of a Ge15Sb20S65 chalcogenide glass microstructured single mode fiber around 1.55 microm. Through a fair comparison between a 2-m long chalcogenide fiber and a 7.9-km long classical single mode silica fiber, we have found a Brillouin and Raman gain coefficients 100 and 180 larger than fused silica, respectively.
<title>Dot-matrix holographic recording in amorphous chalcogenide films</title>
2006
We have developed PC controlled dot-matrix holographic recording system based on the CW diode pumped YAG:Nd SHG laser (wavelength 532 nm, power 30mW,) modulated electronically with TTL signals. Two-beam technique has been used with convergence angle 30o and PC controlled incident beam plane rotation 0-360o. Optical system consists of beam splitter, 40mm focus length forming cylindrical lens and 40mm focusing lens. Characteristic parameters of experimental equipment are following: spot size - 50-200 micrometers, direct laser writing area, limited by x-y positioning system, was 70mm x 70mm, number of writing head rotation positions up to 256 (8 bit), time of each exposure - 1-1000 msec. As th…
Chalcogenide glass hollow core photonic crystal fibers
2010
International audience; We report the first hollow core photonic crystal fibers (HC PCF) in chalcogenide glass. To design the required HC PCF profiles for such high index glass, we use both band diagram analysis to define the required photonic bandgap and numerical simulations of finite size HC PCFs to compute the guiding losses. The material losses have also been taken into account to compute the overall losses of the HC PCF profiles. These fibers were fabricated by the stack and draw technique from Te20As30Se50 (TAS) glass. The fibers we drew in this work are composed of six rings of holes and regular microstructures. Two profiles are presented, one is known as a kagome lattice and the ot…
Selenium Nanoparticles Synthesized via a Facile Hydrothermal Method
2012
Crystalline selenium nanostructures were synthesized from the reaction of a GeSe3 glass with water at 85°C for 144 hours. The hydrolysis of the Ge-Se bonds releases Se fragments in the solution where they form a colloidal suspension of amorphous nanospheres. The later evolve toward a more stable hexagonal phase (trigonal) leading to the anisotropic growth of one-dimensional monocrystalline structures. Filaments, bars and tubes of monocrystalline trigonal selenium were obtained with diameters ranging from 10 nm to 1 µm and aspect ratio up to 180. This simple process in aqueous solution opens new perspectives for the synthesis of 1D nanoparticles of trigonal selenium at large scale.
Design of Er3+-doped chalcogenide glass laser for MID-IR application
2009
Abstract The feasibility of a photonic crystal fiber laser (PCF laser), made of a novel Er 3+ -doped chalcogenide glass and operating at the wavelength λ s = 4.5 μm is investigated. The design is performed on the basis of spectroscopic and optical parameters measured on a fabricated Er 3+ -doped Ga 5 Ge 20 Sb 10 S 65 chalcogenide bulk sample. The simulations have been performed by employing a home made numerical code that solves the multilevel rate equations and the power propagation equations via a Runge-Kutta iterative method. The numerical results indicate that a laser exhibiting slope efficiency close to the maximum theoretical one and a wide tunability in the wavelengths range where t…
Feasibility of Er3+-doped, Ga5Ge20Sb10S65 chalcogenide microstructured optical fiber amplifiers
2009
International audience; The feasibility of a microstructured optical fiber (MOF) amplifier, made of a novel Er3+-doped chalcogenide glass, has been demonstrated via accurate simulations performed by employing an oppositely implemented computer code. The optical and geometrical parameters measured on the first MOF sample together with other physical constants from literature have been taken into account in the simulations. The calculated optical gain of the optimized MOF amplifier, 2.79 m long, is close to 23 dB at the signal wavelength of 1.538 μm, by using a pump power of 200 mW and a signal power of 0.1 μW.
Infrared monitoring of underground CO2 storage using chalcogenide glass fibers
2009
International audience; An optical-fiber-based system suitable for monitoring the presence of carbon dioxide, so-called "greenhouse gas", is investigated. Since each pollutant gas shows a characteristic optical absorption spectrum in the mid-infrared (mid-IR), it is possible to detect selectively and quantitatively the presence of gases in a given environment by analysing mid-IR spectra. The main infrared signature of carbon dioxide gas is a double absorption peak located at 4.2 μm. Chalcogenide optical fibers, which can transmit light in the 1-6 μm range, are well-adapted for CO2 analysis. In this wavelength range, they show attenuation losses that compare favourably with other types of fi…
The kinetics of phase transitions in vitreous chalcogenide semiconductors As10.2Se89.8 and As9Se90Bi in early stage of physical ageing process
2013
The kinetics of glass transition in selenide glasses As10.2Se89.8 and As9Se90Bi in early stage of physical ageing process has been investigated by parallel differential scanning calorimetry (DSC) and exoelectron emission (EEE). It has been found that the glass transition process occurring in investigated glasses is evidenced by peaks on EEE intensity and DSC curves. Admixture of bismuth causes a distinct lowering of the temperature of glass transitions process both in the surface layer and in the volume. The addition of Bi causes a decrease in the value of the activation energy for glass transition process in both the volume and in the surface layer, thus reducing the thermal stability of i…