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Bruno Bureau - One of the best experts on this subject based on the ideXlab platform.
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7 to 8 µm emission from Sm3+ doped Selenide fibers.
Optics Express, 2018Co-Authors: Florent Starecki, Catherine Boussard-plédel, Bruno Bureau, Jean-louis Doualan, Alain Braud, Nora Abdellaoui, Patrice Camy, Virginie NazabalAbstract:: We report on the observation of the long wave-infrared (LWIR) emission centered at 7.3 µm of Sm3+ doped chalcogenide fibers. The chemical composition of the Selenide Glass host matrix (Ga5Ge20Sb10Se65) enables the drawing of 500 ppm and 1000 ppm Sm3+ doped fibers. By means of conventional Glass elaboration methods, these Sm3+ doped fibered materials exhibit a significant emission band from 6.5 to 8.5 µm with a maximum emission around 7.3 µm whether they are excited at 1.45 µm or at 2.05 µm. Absorption spectra, Judd-Ofelt analysis, NIR, MWIR and LWIR luminescence spectra are presented and discussed.
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Selenide Glass fibers for biochemical infrared sensing
2017Co-Authors: Pierre Lucas, Bruno BureauAbstract:This chapter discusses the use of Selenide Glass fibers for biochemical sensing. Selenide Glasses combine two unique properties: (1) high transparency in the mid-infrared, (2) excellent rheological properties for molding and drawing, which make them the most suitable candidate materials for infrared fiber technology. In particular, chalcogenide Glasses exhibit high transparency over the spectral domain corresponding to molecular vibrations and are therefore of great interest for optical sensing applications. Here we review the basic principles of fiber-based spectroscopy and the properties of chalcogenide Glasses such as Selenides. We then review the state of the art in applications of fiber evanescent wave spectroscopy to chemical and biomedical sensing.
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Structure of Arsenic Selenide Glasses Studied by NMR: Selenium Chain Length Distributions and the Flory Model
Journal of Physical Chemistry C, 2015Co-Authors: Michaël Deschamps, Cécile Genevois, Claire Roiland, Laurent Lepollès, Eric Furet, Dominique Massiot, Bruno BureauAbstract:Five homogeneous arsenic Selenide Glasses with target compositions As 2 Se 3 , AsSe 2 , AsSe 3 , AsSe 4.5 , and AsSe 6 were studied quantitatively by 77 Se Carr−Purcell−Meiboom−Gill magic-angle spinning NMR and transmission electron microscopy−energy-dispersive X-ray spectroscopy. The entire set of NMR spectra is simultaneously fitted with six distinct environments taking into account the effect of first and second neighbors on the position of the 77 Se resonance. The selenium chains are bound at each end to trivalent arsenic atoms, and the chain length distribution can be modeled with the Flory theory, which is well-known in polymer science and is used here for the first time to model the probability of finding each selenium environment in a Selenide Glass. No arsenic homopolar bond is detected in our experiments. ■ INTRODUCTION Chalcogenide Glasses exhibit a wide range of physical properties such as infrared transparency, high refractive indices, and reversible amorphous-to-crystal transitions and can be easily shaped into optical devices. 1−6 Among them, the arsenic Selenide Glasses As x Se 1−x are considered to be a promising family because Glassy As 2 Se 3 is a good candidate for all-optical switching 7 or for use as a mid-infrared laser source; 8 in addition, arsenic Selenide Glasses can be used for optic fibers. 9 Recent studies also investigated the possibility of preparing these Glasses using microwave heating. 10 Numerous attempts were made to draw a link between the changes in the physical properties of arsenic Selenide and the evolution of its molecular structure as the arsenic content varies, both at room temperature 11,12 and when the temperature is increased, 13 during aging of the Glass, 14 or when irradiated with a laser. 15 To gain some insight into the arsenic Selenide Glass structures, recent studies relied on molecular dynamics 16−18 combined with anomalous X-ray scattering 19 or 77 Se solid-state NMR 20−23 to characterize the environments and connectivity of selenium and arsenic atoms. Many of these studies hint toward the existence of a small amount of As−As homopolar bond 12,16 with tetravalent arsenic atoms linked to two arsenic and two selenium atoms. 19 Moreover, 77 Se NMR spectroscopy can quantify three distinct selenium environments (selenium atoms linked to two, one, or zero arsenic atoms) and shows that there is some disorder in the distribution of the lengths of the selenium chains that link arsenic atoms together, as opposed to what is inferred in the chain-crossing model (i.e., when the selenium chains are of similar lengths). 20,23 Interestingly, it was suggested that the Flory model, 24 which describes the distribution of chain lengths in organic polymers, could be applied to inorganic polymers (mostly silicates) because the underlying chemical phenomena share striking similarities, especially for Glasses with covalent bonds and no ionic species. 25−27 The Flory theory provides a very simple model for the probability, P(n), of finding a chain of length n, which is equal to np n−1 (1 − p) 2 , where p is the probability to form a linkage between two monomers and the average chain length is given by 1 + p/1 − p. Moreover, Flory distributions are characterized by a single parameter p and not two as is the case for Gaussian distributions (which may not correctly reproduce the chain length distributions for arsenic-rich Glasses with short chain lengths) or three for skewed Gaussian distributions. Therefore, the Flory framework was applied here as a model for the distribution of chain lengths. 77 Se is a spin 1/2 nucleus with a 7.63% natural abundance, a gyromagnetic ratio equal to 19% of γ(1 H), and a fairly large chemical shift range over 3000 ppm. 28,29 However, as many diluted spin-1/2, it usually features long longitudinal relaxation times around hundreds of seconds, which may affect the measured proportions of each selenium environment. 23 Usually, three selenium environments are distinguished depending upon the nature of the two atoms (arsenic or selenium) they are connected with. 20 However, as the 77 Se atoms are excessively sensitive to their environments, it is often observed that the chemical shifts of these broad lines vary with the composition of the sample, 20 precluding any simultaneous fitting of series of NMR spectra. Such an effect results from a dependence of the
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Structure of Arsenic Selenide Glasses Studied by NMR: Selenium Chain Length Distributions and the Flory Model
Journal of Physical Chemistry C, 2015Co-Authors: Michaël Deschamps, Cécile Genevois, Claire Roiland, Laurent Lepollès, Eric Furet, Dominique Massiot, Bruno BureauAbstract:Five homogeneous arsenic Selenide Glasses with target compositions As2Se3, AsSe2, AsSe3, AsSe4.5, and AsSe6 were studied quantitatively by 77Se Carr–Purcell–Meiboom–Gill magic-angle spinning NMR and transmission electron microscopy–energy-dispersive X-ray spectroscopy. The entire set of NMR spectra is simultaneously fitted with six distinct environments taking into account the effect of first and second neighbors on the position of the 77Se resonance. The selenium chains are bound at each end to trivalent arsenic atoms, and the chain length distribution can be modeled with the Flory theory, which is well-known in polymer science and is used here for the first time to model the probability of finding each selenium environment in a Selenide Glass. No arsenic homopolar bond is detected in our experiments.
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Development of optical fibers for mid-infrared sensing: state of the art and recent achievements
Proceedings of SPIE, 2015Co-Authors: Bruno Bureau, Catherine Boussard-plédel, Virginie Nazabal, Johann Troles, Jean-louis Doualan, Pierre Lucas, Alain Braud, Patrice Camy, Jean Adam, Laurent BrillandAbstract:Chalcogenide Glass fibers are matchless devices to collect mi-infrared signal. Depending on the spectroscopic strategy, different kind of optical fibers have been developed during the past 10 years. The first fibers have been fabricated from Selenide Glasses to implement Fiber Evanescent Wave Spectroscopy (FEWS). It is an efficient way to collect optical spectra in situ, in real time and even, in the future, in vivo. Thanks to Selenide Glass fibers, it is possible to record such spectra on the mid-infrared range from 2 to 11 μm. This working window gives access to the fundamental vibration band of most of biological molecules and numerous multi-disciplinary works have been led in biology and medicine. New Glasses, only based on tellurium, have been recently developed, initially in the frame of the Darwin mission led by the European Space Agency (ESA). These Glasses transmit light further toward the farinfrared and permit to reach the absorption band of CO2 located at 15 μm as requested by the ESA. Moreover, these telluride Glass fiber are also very interesting for FEWS and medical application. Indeed, they give access to the mid-infrared signal of biomolecules beyond 11 μm, where classical Selenide Glass fibers are blind. Alternatively, in order to fight against global warning, some optical fibers have been developed for the monitoring of the CO2 stored into geological storage area underground. These fibers were doped with Dy3+ which emits a broad fluorescent band embedding the CO2 absorption band at 4.3 μm. thus, these fibers are used both to transmit light and as secondary sources in the mid-infrared. To conclude, original microstructurated fibers have also been used for mid-infrared sensing. They exhibit a nice sensitivity compared to classical chalcogenide Glass fibers.
I.d. Aggarwal - One of the best experts on this subject based on the ideXlab platform.
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Fabrication of Arsenic Sulfide Optical Fiber with Low Hydrogen Impurities
Journal of the American Ceramic Society, 2002Co-Authors: Vinh Q. Nguyen, B. Cole, Jas S. Sanghera, Pablo C. Pureza, Frederic H. Kung, I.d. AggarwalAbstract:Arsenic Selenide Glass optical fibers typically possess extrinsic absorption bands in the infrared wavelength region associated with residual hydrogen and oxygen related impurities, despite using purified precursors. We report a purification process based on the addition of 0.1 wt% tellurium tetrachloride (TeCl4) to the Glass. During melting, the chlorine from TeCl4 reacts with the hydrogen impurities to produce volatile products (e.g., HCl) that can be removed by subsequent dynamic distillation. The processing conditions have been modified accordingly to give very low H–Se impurity content. Consequently, the H–Se absorption band centered at 4.57 μm has been reduced from tens of dB/m to 0.2 dB/m.
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Rare-earth-doped Selenide Glass optical sources
Technical Digest. Summaries of Papers Presented at the Conference on Lasers and Electro-Optics. Conference Edition. 1998 Technical Digest Series Vol.6, 1998Co-Authors: L.b. Shaw, B. Cole, D.t. Schaafsma, B.b. Harbison, J.s. Sanghera, I.d. AggarwalAbstract:Summary form only given. We have discussed the applicability of rare-earth-doped Selenide Glasses for mid-IR laser, superfluorescent, and fiber sources. The feasibility of these Glasses as phosphor sources for chemical sensing has been demonstrated.
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rare earth doped Selenide Glass optical sources
Conference on Lasers and Electro-Optics, 1998Co-Authors: L.b. Shaw, B. Cole, D.t. Schaafsma, B.b. Harbison, J.s. Sanghera, I.d. AggarwalAbstract:We have discussed the applicability of rare-earth-doped Selenide Glasses for mid-IR laser, superfluorescent, and fiber sources. The feasibility of these Glasses as phosphor sources for chemical sensing has been demonstrated.
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dy doped Selenide Glass for 1 3 spl mu m optical fiber amplifiers
Optical Fiber Communication Conference, 1998Co-Authors: L.b. Shaw, B. Cole, J.s. Sanghera, I.d. Aggarwal, D.t. SchaafsmaAbstract:Summary form only given. Dy/sup 3+/-doped materials have been proposed for optical fibre amplifiers at 1.3 μm. Dy/sup 3+/ has several advantages over Pr/sup 3+/-based amplifiers for 1.3-μm telecommunication applications. First, numerous pump bands exist in the near-IR for populating the (/sup 6/H/sub 9/2/, /sup 6/F/sub 11/2/) level. Secondly, these pump bands have absorption coefficients >10 times that of the Pr/sup 3+/ /sup 1/G/sub q/ level in the same host.
A B Seddon - One of the best experts on this subject based on the ideXlab platform.
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mid infrared emission in tb 3 doped Selenide Glass fiber
Journal of The Optical Society of America B-optical Physics, 2017Co-Authors: L Sojka, Zhuoqi Tang, H. Sakr, D Furniss, Y Fang, E Berespawlik, T M Benson, A B Seddon, S SujeckiAbstract:The mid-infrared (MIR) emission behavior of Tb3+-doped Ge–As–Ga–Se bulk Glasses (500, 1000, and 1500 ppmw Tb3+) and unstructured fiber (500 ppmw Tb3+) is investigated when pumping at 2.013 μm. A broad emission band is observed at 4.3–6.0 μm corresponding to F57→F67, with an observed emission lifetime of 12.9 ms at 4.7 μm. The F47 level is depopulated nonradiatively and so it is proposed that Tb3+-doped Ge–As–Ga–Se fiber may operate as a quasi-three-level MIR fiber laser. Underlying Glass-impurity vibrational absorption bands are numerically removed to give the true Tb3+ absorption cross section, as required for Judd–Ofelt (J–O) analysis. Radiative transition rates calculated from J–O theory are compared with measured lifetimes. A numerical model of the three-level Tb3+-doped fiber laser is developed for Tb3+ doping of 8.25×1024 ions m−3 (i.e., 500 ppmw) and dependence of laser performance on fiber length, output coupler reflectivity, pump wavelength, signal wavelength, and fiber background loss is calculated. Results indicate the feasibility of an efficient three-level MIR fiber laser operating within 4.5–5.3 μm, pumped at either 2.013 or 2.95 μm.
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the influence of dysprosium addition on the crystallization behavior of a chalcogenide Selenide Glass close to the fiber drawing temperature
Journal of the American Ceramic Society, 2012Co-Authors: Yin Cheng, Zhuoqi Tang, D Furniss, T M Benson, Nigel C Neate, A B SeddonAbstract:A series of chalcogenide Glasses based on Ge16.5Ga3As16Se64.5 (at.%), doped nominally with 0, 1000, 3000, and 6000 ppmw (by weight) of Dy foil, is prepared by using conventional method: melting inside a sealed silica Glass ampoule, which is rocked to homogenize the melt, followed by melt quenching and annealing. Examination of the as-prepared Glasses, using scanning electron microscopy with energy dispersive X-ray spectroscopy (SEM-EDX), reveals that dysprosium-rich areas of devitrification have a tendency to form at the surfaces of the prepared chalcogenide Glasses which have been adjacent the silica ampoule walls during the final stages of melting, quenching, and annealing; such dysprosium-rich areas of devitrification are not observed using SEM-EDX at the noncontacting-silica-ampoule chalcogenide Glass surface nor in the interior of the chalcogenide Glass bulk. Samples taken from the interior of the prepared Glass boules exhibit an increase in Glass transition of up to 9 ± 2°C, and rise in other isoviscous temperatures, with increasing dysprosium content. Extended isothermal heat treatment at the estimated fiber-drawing temperature, followed by quenching to room temperature and analysis using SEM-EDX and X-ray diffraction (XRD), is carried out to investigate the influence of dysprosium addition on crystallization behavior on reheating the chalcogenide Glass. Increasing the dysprosium level, surprisingly, appears on the one hand to help to restrain crystallization of the bulk Glass on Glass reheating, whereas on the other hand, and at the same time, to exacerbate the surface devitrification on Glass reheating. The bulk crystallizing phase on reheating the Glasses is distorted face-centered cubic α-Ga2Se3. The same phase was found to grow in the bulk Glass during melt cooling of Dy-doped Ge–As–Ga–Se Glasses in our earlier work.
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First-time microwave-synthesis of As40Se60 chalcogenide Glass: With potential for mid-infrared photonics
2010 12th International Conference on Transparent Optical Networks, 2010Co-Authors: N. Prasad, A B SeddonAbstract:As40Se60 Glass is synthesised in ≤ 35 min via microwave heating in a domestic microwave oven (DMO). The DMO product is compared with arsenic Selenide Glass made by conventional resistive furnace melting which takes > 30 h to produce homogeneous chalcogenide Glass. X-ray diffraction, transmission electron microscopy with selected area electron diffraction, analytical scanning electron microscopy optical microscopy and differential thermal analysis indicate that the DMO As40Se60 has similar properties to those of the conventionally melted As40Se60 Glass. Fourier transform infrared spectroscopy and refractive index dispersion show slight differences. The DMO As40Se60 Glass is patterned, using hot embossing, and is drawn to fibre.
Zhuoqi Tang - One of the best experts on this subject based on the ideXlab platform.
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Spatiotemporal modeling of mid-infrared photoluminescence from terbium(III) ion doped chalcogenide-Selenide multimode fibers
Journal of Rare Earths, 2019Co-Authors: Slawomir Sujecki, Lukasz Sojka, Zhuoqi Tang, David Furniss, Emma R. Barney, Trevor M. Benson, D. Jayasuriya, Angela B. SeddonAbstract:Abstract A numerical model was developed to study the time dynamics of photoluminescence emitted by Tb3+ doped multimode chalcogenide-Selenide Glass fibers pumped by laser light at approximately 2 μm. The model consists of a set of partial differential equations (PDEs), which describe the temporal and spatial evolution of the photon density and level populations within the fiber. In order to solve numerically the PDEs a method of lines was applied. The modeling parameters were extracted from measurements and from data available in the literature. The numerical results obtained support experimental observations. In particular, the developed model reproduces the discrepancies that are observed between the photoluminescence decay curves obtained from different points along the fiber. The numerical analysis was also used to explain the source of these discrepancies.
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Experimental and numerical investigation to rationalize both near-infrared and mid-infrared spontaneous emission in Pr3+ doped Selenide-chalcogenide fiber
Journal of Luminescence, 2019Co-Authors: Slawomir Sujecki, Lukasz Sojka, Elzbieta M. Beres-pawlik, Krzysztof Anders, Ryszard Piramidowicz, Zhuoqi Tang, David Furniss, Emma R. Barney, Trevor M. Benson, Angela B. SeddonAbstract:Abstract This contribution reports on detailed experimental and numerical investigations of both near-infrared (NIR) and mid-infrared (MIR) photoluminescence obtained in praseodymium trivalent ion doped chalcogenide-Selenide Glass fiber. The experimental analysis allows for the identification of the radiative transitions within the praseodymium ion energy level structure to account for the photoluminescent behavior. Numerical analysis is carried out using the rate equations’ approach to calculate the level populations. The numerical analysis provides further insight into the nature of the radiative transitions in the Pr3+ ion doped chalcogenide-Selenide Glass and allows for the identification of the electronic transitions, which contribute to the observed photoluminescence. The numerical results agree well with the experimental results.
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Numerical analysis of spontaneous mid-infrared light emission from terbium ion doped multimode chalcogenide fibers
Journal of Luminescence, 2018Co-Authors: Slawomir Sujecki, Lukasz Sojka, Krzysztof Anders, Ryszard Piramidowicz, Zhuoqi Tang, David Furniss, Emma R. Barney, Trevor M. Benson, Elzbieta Pawlik, Angela B. SeddonAbstract:Abstract In this contribution we use a numerical model to study the photoluminescence emitted by Tb3+ doped chalcogenide-Selenide Glass fibers pumped by laser light at approximately 3 µm. The model consists of the set of ordinary differential equations (ODEs), which describe the spatial evolution of the pump laser and MIR photoluminescence light within the fiber. The ODEs are coupled with the rate equations that describe the energy level populations. A self-consistent solution of the equation system yields the pump light, MIR photoluminescence and level population distribution within the fiber. Using the developed model we numerically calculate results and discuss the dependence of the output photoluminescence MIR power on the fiber optical loss, fiber length and pump wavelength.
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A study of MIR photoluminescence from Pr3+ doped chalcogenide fibers pumped at near-infrared wavelengths
12th Conference on Integrated Optics: Sensors Sensing Structures and Methods, 2017Co-Authors: Slawomir Sujecki, Lukasz Sojka, Elzbieta M. Beres-pawlik, Ryszard Piramidowicz, Zhuoqi Tang, David Furniss, Emma R. Barney, Trevor M. Benson, H. Sakr, Angela B. SeddonAbstract:We perform a numerical analysis of mid-infrared photoluminescence emitted by praseodymium (III) doped chalcogenide Selenide Glass pumped at near-infrared wavelengths. The results obtained show that an effective inversion of level populations can be achieved using both 1480 nm and 1595 nm laser diodes. The rate of the spontaneous emission achieved when pumping at 1480 nm and 1595 nm is comparable to this achieved using the standard pumping wavelength of 2040 nm.
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mid infrared emission in tb 3 doped Selenide Glass fiber
Journal of The Optical Society of America B-optical Physics, 2017Co-Authors: L Sojka, Zhuoqi Tang, H. Sakr, D Furniss, Y Fang, E Berespawlik, T M Benson, A B Seddon, S SujeckiAbstract:The mid-infrared (MIR) emission behavior of Tb3+-doped Ge–As–Ga–Se bulk Glasses (500, 1000, and 1500 ppmw Tb3+) and unstructured fiber (500 ppmw Tb3+) is investigated when pumping at 2.013 μm. A broad emission band is observed at 4.3–6.0 μm corresponding to F57→F67, with an observed emission lifetime of 12.9 ms at 4.7 μm. The F47 level is depopulated nonradiatively and so it is proposed that Tb3+-doped Ge–As–Ga–Se fiber may operate as a quasi-three-level MIR fiber laser. Underlying Glass-impurity vibrational absorption bands are numerically removed to give the true Tb3+ absorption cross section, as required for Judd–Ofelt (J–O) analysis. Radiative transition rates calculated from J–O theory are compared with measured lifetimes. A numerical model of the three-level Tb3+-doped fiber laser is developed for Tb3+ doping of 8.25×1024 ions m−3 (i.e., 500 ppmw) and dependence of laser performance on fiber length, output coupler reflectivity, pump wavelength, signal wavelength, and fiber background loss is calculated. Results indicate the feasibility of an efficient three-level MIR fiber laser operating within 4.5–5.3 μm, pumped at either 2.013 or 2.95 μm.
I.d. Aggarwal - One of the best experts on this subject based on the ideXlab platform.
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Effect of heating on the optical loss in the As-Se Glass fiber
Journal of Lightwave Technology, 2003Co-Authors: V.q. Nguyen, J.s. Sanghera, P.c. Pureza, I.d. AggarwalAbstract:The increase in the optical loss of the IR-transmitting arsenic-Selenide Glass fiber in the temperature range of 150/spl deg/C /spl ges/T/spl ges/ 20/spl deg/C was investigated. Between the wavelength region of 1.3 and 8 /spl mu/m, there is a small increase in the loss in which the contribution of free-carrier absorption is small. At high temperature T=150/spl deg/C and /spl lambda//spl ges/8 /spl mu/m, both the free-carrier and multiphonon absorption contributed to the total loss. From a practical perspective, the As-Se fiber loss increases only slightly under normal operating temperatures and so can still be used for many applications.
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Effect of heating on the optical loss in the As-Se Glass fiber
Journal of Lightwave Technology, 2003Co-Authors: V.q. Nguyen, J.s. Sanghera, P.c. Pureza, I.d. AggarwalAbstract:The increase in the optical loss of the IR-transmitting arsenic-Selenide Glass fiber in the temperature range of 150°C /spl ges/T/spl ges/ 20°C was investigated. Between the wavelength region of 1.3 and 8 μm, there is a small increase in the loss in which the contribution of free-carrier absorption is small. At high temperature T=150°C and /spl lambda//spl ges/8 μm, both the free-carrier and multiphonon absorption contributed to the total loss. From a practical perspective, the As-Se fiber loss increases only slightly under normal operating temperatures and so can still be used for many applications.
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Dy-doped Selenide Glass for 1.3-/spl mu/m optical fiber amplifiers
OFC '98. Optical Fiber Communication Conference and Exhibit. Technical Digest. Conference Edition. 1998 OSA Technical Digest Series Vol.2 (IEEE Cat. N, 1998Co-Authors: L.b. Shaw, J.s. Sanghera, I.d. Aggarwal, B.j. Cole, D.t. SchaafsmaAbstract:Summary form only given. Dy/sup 3+/-doped materials have been proposed for optical fibre amplifiers at 1.3 μm. Dy/sup 3+/ has several advantages over Pr/sup 3+/-based amplifiers for 1.3-μm telecommunication applications. First, numerous pump bands exist in the near-IR for populating the (/sup 6/H/sub 9/2/, /sup 6/F/sub 11/2/) level. Secondly, these pump bands have absorption coefficients >10 times that of the Pr/sup 3+/ /sup 1/G/sub q/ level in the same host.