Materials Letters 101(2013)21-24 Contents lists available at sciverse scienceDirect materials letters Materials letters ELSEVIER journalhomepagewww.elsevier.com/locate/matlet Mid-IR luminescence of Dy+ and Pr+ doped Gas Gez0Sb10S(Se)65 bulk glasses and fibers F. Charpentier F Starecki, J.L. Doualan P Jovari, P. Camy b, J. Roles a, S Belin, B. bureau V. Nazabal s Equipe Verres 8 Ceramiques-Institut des Sciences chimiques de rennes, UMR 6226-Universite de Rennes 1-CNRS, 35042 Renne Institute for Solid State Physics and Optics, wigner Research Centre, Hungarian Academy of Sciences, H-1525 Budapest, A0B4y,.n, france Centre de Recherche sur les lors, les Materiaux et la photonique(CIMAP). UMR 6252 CEA-CNRS-ENSICaen, Universite de Caen, 14050 Saint Aubin. 9119 92 Gif sur Yvette, france ARTICLE INF O A BSTRACT Received 22 December 2012 (mid-IR). The complex glassy network of these chalcogenide glasses were characterized by Raman attering and extended X-ray absorption fine structure, to put in evidence a structure combining Available online 21 march 2013 tetrahedra of Germanium and Gallium and trigonal pyramids of Antimony. The arrangement of these structural units permits the introduction of rare earth ions thanks, in particular, to a charge compensa- on generated by the Ga in a tetrahedral site. Consequently. Pr+ and Dy+ ions inserted in such low phonon energy glasses emit efficiently in mid-IR, between 3.5 and 5 um. Finally Dy+ and Pr+ doped EXAFS GasGe2oSb10S(Se)65 fibers were obtained from bulk glass preform. Efficient emission in mid-IR was Mid-IR emission obtained by pumping Dy+ doped Gas Sb1oSs5 and Pr+ doped Gas Ge2o Sb10 S(Se)65 fibers at 920 nm Dysprosium and 2 um, respectively. e 2013 Elsevier B.V. All rights reserved. Introduction scalability if the selenide double-clad fiber optical loss remains lower than 5 dB/m [5]. The Pr+ also offers several transitions Mid-infrared(mid-IR)radiation, often generated by black body which give a broad emission spectrum between 3.5 and 5.5 um sources in optical sensors, possesses low brightness influenced by [1-3, 6. Selected Ga-Ge-Sb-S(Se)glasses doped with RE can be the surrounding Black body sources can be efficiently replaced by shaped in optical waveguides, like rib waveguides or conventional emission from rare earth(RE)ions [1] for which the brightness is fibers 3, 8, 10-13] and light can be easily confined, thanks to their relatively temperature independent changing mainly according optical pump source scheme and matrix nature. For potential 1.55 um). Moreover, in such glasses, the incorporation of RE ions is applications in this spectral range, the re mid-IR emission require possible up to 1 wt by keeping the amorphous state of the the use of material host with low phonon energy as sulfide and materials which is favorable for applications such as highly bright selenide matrices for instance[1-6]. Disordered glassy network incoherent sources. In the present paper, the amorphous structure lower the Re site symmetry and facilitate the mixing of orbitals by of complex quaternary GasGe S(Se)65 glasses will be allowing f-f transitions of RE ions. Consequently, the emission is described in relation to the spectroscopic properties of Dy+ and broad and non-structured unlike glass-ceramics [7 which is t incorporated in mentioned glasses. favorable for differential detection techniques in optical sensors. Moreover, optical waveguides can be made of chalcogenide glasses which increase the brightness of the fluorescent source. Among all 2. Materials and methods RE, Dy+ presents an emission band centered at 4.35 um corre- nding to the transition between the H1 and H1/2 levels The selected glass composition is GasGez0Sb1oS(Se)6s doped by [2,8, 9l. which can be efficiently pumped by commercial laser Dy+ or Pr+ ions from 0.05 to 1 wt%. After sealing, the chemical diodes. It was proposed by numerical modeling that simultaneous reagents in the silica tul e slowly heated to 900C durin ing at 1.7 um significantly improves the efficiency and power The 300-400 um diameter fibers were obtained by drawing length which were doped with 0.05 or 0. 1 wt of RE [12 orresponding author. Tel:+33223235748: fax: +33223235611 Absorption spectra were measured on bulk glasses with Perkin Elmer spectrometer Lambda-1050. A Ti: Sapphire laser emitting at 0167-577x/S-see fr e 2013 Elsevier B v. All rights reserved.Mid-IR luminescence of Dy3þ and Pr3þ doped Ga5Ge20Sb10S(Se)65 bulk glasses and fibers F. Charpentier a , F. Starecki b , J.L. Doualan b , P. Jóvári c , P. Camy b , J. Troles a , S. Belin d , B. Bureau a , V. Nazabal a,n a Equipe Verres & Céramiques—Institut des Sciences chimiques de Rennes, UMR 6226-Université de Rennes 1-CNRS, 35042 Rennes, France b Centre de Recherche sur les Ions, les Matériaux et la Photonique (CIMAP), UMR 6252 CEA-CNRS-ENSICaen, Université de Caen, 14050 Caen, France c Institute for Solid State Physics and Optics, Wigner Research Centre, Hungarian Academy of Sciences, H-1525 Budapest, POB 49, Hungary d Synchrotron SOLEIL, L'Orme des Merisiers, Saint Aubin, 91192 Gif sur Yvette, France article info Article history: Received 22 December 2012 Accepted 11 March 2013 Available online 21 March 2013 Keywords: Chalcogenide glass Fiber EXAFS Mid-IR emission Praseodymium Dysprosium abstract Dy3þ and Pr3þ doped Ga5Ge20Sb10S(Se)65 glasses provide good emission efficiencies in the mid-infrared (mid-IR). The complex glassy network of these chalcogenide glasses were characterized by Raman scattering and extended X-ray absorption fine structure, to put in evidence a structure combining tetrahedra of Germanium and Gallium and trigonal pyramids of Antimony. The arrangement of these structural units permits the introduction of rare earth ions thanks, in particular, to a charge compensa￾tion generated by the Ga in a tetrahedral site. Consequently, Pr3þ and Dy3þ ions inserted in such low phonon energy glasses emit efficiently in mid-IR, between 3.5 and 5 μm. Finally, Dy3þ and Pr3þ doped Ga5Ge20Sb10S(Se)65 fibers were obtained from bulk glass preform. Efficient emission in mid-IR was obtained by pumping Dy3þ doped Ga5Ge20Sb10S65 and Pr3þ doped Ga5Ge20Sb10S(Se)65 fibers at 920 nm and 2 μm, respectively. & 2013 Elsevier B.V. All rights reserved. 1. Introduction Mid-infrared (mid-IR) radiation, often generated by black body sources in optical sensors, possesses low brightness influenced by the surrounding. Black body sources can be efficiently replaced by emission from rare earth (RE) ions [1] for which the brightness is relatively temperature independent changing mainly according to optical pump source scheme and matrix nature. For potential applications in this spectral range, the RE mid-IR emission require the use of material host with low phonon energy as sulfide and selenide matrices for instance [1–6]. Disordered glassy network lower the RE site symmetry and facilitate the mixing of orbitals by allowing f–f transitions of RE ions. Consequently, the emission is broad and non-structured unlike glass-ceramics [7] which is favorable for differential detection techniques in optical sensors. Moreover, optical waveguides can be made of chalcogenide glasses which increase the brightness of the fluorescent source. Among all RE, Dy3þ presents an emission band centered at 4.35 mm corre￾sponding to the transition between the 6 H11/2 and 6 H13/2 levels [2,8,9], which can be efficiently pumped by commercial laser diodes. It was proposed by numerical modeling that simultaneous lasing via 6 H11/2-6 H13/2 and 6 H13/2-6 H15/2 transitions by pump￾ing at 1.7 μm significantly improves the efficiency and power scalability if the selenide double-clad fiber optical loss remains lower than 5 dB/m [5]. The Pr3þ also offers several transitions which give a broad emission spectrum between 3.5 and 5.5 μm [1–3,6]. Selected Ga–Ge–Sb–S(Se) glasses doped with RE can be shaped in optical waveguides, like rib waveguides or conventional fibers [3,8,10–13] and light can be easily confined, thanks to their high refractive index (2.25 for sulfides and 2.58 for selenides at 1.55 mm). Moreover, in such glasses, the incorporation of RE ions is possible up to 1 wt % by keeping the amorphous state of the materials which is favorable for applications such as highly bright incoherent sources. In the present paper, the amorphous structure of complex quaternary Ga5Ge20Sb10S(Se)65 glasses will be described in relation to the spectroscopic properties of Dy3þ and Pr3þ incorporated in mentioned glasses. 2. Materials and methods The selected glass composition is Ga5Ge20Sb10S(Se)65 doped by Dy3þ or Pr3þ ions from 0.05 to 1 wt%. After sealing, the chemical reagents in the silica tube were slowly heated to 900 1C during several hours, followed by water quenching and annealing [12,13]. The 300–400 mm diameter fibers were obtained by drawing Ga–Ge–Sb–S(Se) glass preforms of 12 mm diameter and 100 mm length which were doped with 0.05 or 0.1 wt % of RE [12]. Absorption spectra were measured on bulk glasses with Perkin Elmer spectrometer Lambda-1050. A Ti:Sapphire laser emitting at Contents lists available at SciVerse ScienceDirect journal homepage: www.elsevier.com/locate/matlet Materials Letters 0167-577X/$ - see front matter & 2013 Elsevier B.V. All rights reserved. http://dx.doi.org/10.1016/j.matlet.2013.03.062 n Corresponding author. Tel.: þ33223235748; fax: þ33223235611. E-mail address: virginie.nazabal@univ-rennes1.fr (V. Nazabal). Materials Letters 101 (2013) 21–24