Luminescence of the Yb-doped PbO–Bi 2 O 3 –Ga 2 O 3 –BaO glasses K.J. Pluci  nski a , W. Gruhn b , J. Wasylak c , J. Ebothe d , D. Dorosz c , J. Kucharski c , I.V. Kityk b, * a Electronics Department, Military Academy of Technology, ul. Kaliskiego 2, 00-908 Warszawa, Poland b Institute of Physics, WSP, Al. Armii Krajowej 13/15, 42-201 Cze ßstochowa, Poland c Glass and Ceramics Department, University of Meaning and Metallurgy, Al. Mickiewicza 30, 30-059 Krak ow, Poland d Universit e de Reims, UFR Science Exactes, UTAP-LMET, UPRES EA n° 2061, 21, rue Cl ement Ader, B.P. 138, 51685 Reim Cedex 02, France Received 27 August 2001; received in revised form 19 August 2002; accepted 5 September 2002 Abstract Luminescence and absorption at wavelengths 600–1000 nm from Yb 3þ ions embedded in PbO–Bi 2 O 3 –Ga 2 O 3 –BaO glass hosts is reported at room and helium liquid temperatures. We have found that excited pulsed XeII laser light (k ¼ 714 nm) gives substantial luminescence at 980 nm with efficiency up to 63.2%. Kinetics of luminescence gives a decay time about 1050 ls. Explanation of the obtained results is presented within the framework of the Judd–Ofelt method and inclusion of electron–phonon anharmonicity. Ó 2002 Elsevier Science B.V. All rights reserved. PACS: 42.70; 78.60; 71.20.E Keywords: Luminescence; Earth-doped glasses; Photoabsorption of the doped glasses; PbO–Bi 2 O 3 –Ga 2 O 3 –BaO–Yb glasses 1. Introduction It has been shown recently [1–3] that heavy metal oxide (HMO) glasses are very attractive hosts for rare-earth (RE) ions. Among the HMO glasses more interesting are PbO–Bi 2 O 3 –Ga 2 O 3 – BaO–Yb (PBG) glasses [4,5] because they possess high transparency (up to 60%) within the 0.6–8.7 lm spectral range. Mainly PbO and Bi 2 O 3 oxides [5,6] determine their optical properties. Introduc- tion of Ga 2 O 3 favours increasing thermo-stability of the glasses [7,8]. We have found [4,5] that the optimal transparency of the glasses corresponds to the composition: PbO(0.30)–Bi 2 O 3 (0.25)–Ga 2 O 3 (0.36)–BaO(0.09). We have synthesised both bulk- like specimens in the form of parallelepiped (8  8  1 mm) as well film specimens (thickness vary- ing 0.5–15 lm) deposited on the quartz substrates. This glass has a glass transition temperature (640 K) and a large thermal expansion coefficient (123  10 7 K 1 ) with refractive index 2.154 (for the wavelength 633 nm). All of these features put the mentioned glasses among the promising materials for manufacturing of optical fiber in the * Corresponding author. E-mail address: i.kityk@wsp.czest.pl (I.V. Kityk). 0925-3467/02/$ - see front matter Ó 2002 Elsevier Science B.V. All rights reserved. PII:S0925-3467(02)00232-X Optical Materials 22 (2003) 13–19 www.elsevier.com/locate/optmat