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The nature of intrinsic luminescence in glasses and crystals of CaO-Ga2O3-GeO2 system 
Padlyak B.

Institute of Physical Optics, 23 Dragomanov St., 79005, Lviv, Ukraine

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Keywords: germanate glasses, Ca3Ga2Ge3O12 garnet, intrinsic luminescence, synchrotron radiation, luminescence kinetics, recombination mechanism, radiation-induced defects, electron spin resonance (ESR)

PACS: 42.70.Ce, 07.85.Qe; 78.55.Hx, 76.30.Mi.

Ukr. J. Phys. Opt. 8 235-248                   
doi: 10.3116/16091833/8/4/235/2007
Received: 14.11.2007

Intrinsic luminescence of undoped glasses and crystals of CaO-Ga2O3-GeO2 system with different compositions is investigated. Using synchrotron excitation, the emission and time-resolved luminescence excitation spectra, as well as the luminescence kinetics are studied at T = 8 K for the undoped glasses and crystals with garnet Ca3Ga2Ge3O12 composition and the glasses with Ca3Ga2O6 composition. The observed luminescence spectra strongly depend on the basic glass composition and the excitation energy. They consist of several (up to four) broad emission bands located in the visible spectral range. Basing on comparative analysis of the emission and excitation spectra and the decay kinetics in the glasses and crystals of CaO-Ga2O3-GeO2 system, we propose recombination mechanism of the intrinsic luminescence. Specific models suggested for the intrinsic luminescence are supported by electron spin resonance spectroscopic results


1. Damen JPM, .Pistorius JA and Robertson JM, 1977. Calcium-Gallium-Germanium Garnet as a Substrate for Magnetic Bubble Applications. Mater. Res. Bull. 12: 73–75.
2. Mill BV, Butashin AV, Ellern AM and Majer AA, 1981. Phases Formation in CaO-Ga2O3-GeO2 System. Izv. Akad. Nauk SSSR, Ser. Neorgan. Mater. 17: 1648–1653.
3. Mill BV, Butashin AV and Ellern AM, 1983. Germanates with Ca3Ga2Ge4O14 Structure. Izv. Akad. Nauk SSSR, Ser. Neorgan. Mater. 19: 1715–1717.
4. Padlyak BV and Buchynskii PP, 1998. Glass Transparent in the Infrared Region. Patent of Ukraine, No. UA 25235 A.
5. Jeevaratnam J and Glasser FP, 1961. The System CaO – Ga2O3. J. Amer. Ceram. Soc. 44: 563–566.
6. Padlyak B, Mudry S, Halchak V, Korolyshyn A, Rybicki J, Witkowska A, 2000. The Structure of CaO-Ga2O3-GeO2 Glasses: X-ray and Molecular Dynamics Simulation Studies. Opt. Appl. XXX: 691–699.
7. Chelstowski D, Witkowska A, Rybicki J, Padlyak B, Trapananti A and Principi E, 2003. EXAFS Study of Glasses of the CaO-Ga2O3-GeO2 System. Opt. Appl. XXXIII: 125–132.
8. Henderson B. and Wertz J.E. Defects in the Alkaline Earth Oxides. London: Taylor and Francis Ltd. (1977).
9. Padlyak BV, Bordun OM and Buchynskii PP, 1998. Intrinsic Luminescence of the Undoped Glasses of CaO-Ga2O3-GeO2 System. Acta Phys. Pol. A 95: 921–929.
10. Padlyak BV and Kuklinski B, 2004. Nature of Intrinsic Luminescence in the Glasses of CaO-Ga2O3-GeO2 System. Radiat. Meas. 38: 593–597.
11. Zimmerer G, 1991. Status Report on Luminescence Investigations with Synchrotron Radiation at HASYLAB . Nucl. Instr. and Meth. A. 308: 178–186.
12. Padlyak BV, 2003. Radiation-Induced Centres in Glasses of the CaO-Ga2O3-GeO2 System. Radiation Effects and Defects in Solids 158: 411–418.
13. Padlyak B, Vlokh O and Jungner H, 2005. Thermally Stimulated Luminescence of Radiation-Induced Defects in the Glasses of CaO-Ga2O3-GeO2 System. Ukr. J. Phys. Opt. 6: 55–62.
14. Padlyak BV, Jungner H, Fabisiak K and Dubelt SP, 2006. Radiation-Induced Defects in Glasses and Ceramics of the CaO-Ga2O3-GeO2 System. Rev. Adv. Mater. Sci. 12: 97–105.
15. Nosenko AE and Padlyak BV, 1989. Low-Temperature Radiation-Generated Paramagnetic Centers in Ca3Ga2Ge3O12 Crystals. Sov. Phys.: Solid State 31: 317–319.
16. Nosenko AE, Leshchuk RYe and Padlyak BV and Sel’skii AA, 1997. Radiation-Induced Paramagnetic Centers in Ca3Ga2Ge4O14 Crystals. Phys. Solid State 39: 938–942.
17. Poulios DP, Spoonhower JP and Bigelow NP, 2003. Influence of Oxygen Deficiencies and Hydrogen-Loading on Defect Luminescence in Irradiated Ge-doped Silica Glasses. J. Lumin. 101: 23–33.
18. Anedda A, Carbonaro CM, Clemente F, Corpino R and Serpi A, 2003. Excitation Pattern of the Blue Emission in Ge-Doped Silica. J. Non-Cryst. Solids 315: 161–165.
19. Griscom D.L. Defects and Their Structure in Nonmetallic Solids. Eds. Henderson B. and Hugs A.E. New York: Plenum Press (1976).
20. Griscom DL, 1980. Defects in Glasses. J. Non-Cryst. Solids 40: 211–269.

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