Optics & Laser Technology 33 (2001) 157–160 www.elsevier.com/locate/optlastec Eu 3+ -dopedglassmaterialsforredluminescence I.V.Kityk a ; ∗ ,J.Wasylak b ,D.Dorosz b ,J.Kucharski b a Institute of Physics WSP Czestochowa, Al. Armii Krajowej 13=15, Poland b Department of Glass and Ceramics, Academy of Mining and Metalurgy, Al.Mickiewicza 30, Krakow, Poland Received 2 January 2001; accepted 19 January 2001 Abstract Red luminescence (at wavelength about 622 nm) from Eu 3+ ions embedded in PbO–Bi2O3–Ga2O3–BaO glass hosts is reported for room and liquid helium temperatures. The substantial inuence of energy transfer processes between the host and Eu 3+ ions is shown experimentally through the dependences of photoluminescence on light polarization and excitation wavelength. Only polarized, excited pulsedXeIIlaserlight( =714nm)givessubstantialluminescencewitheciencyupto14.3%.Theroleofphonon-relaxationsubsystem in the observed luminescence is discussed. c  2001 Elsevier Science Ltd. All rights reserved. PACS: 42.70; 78.60; 71.20E Keywords: Glasses; Luminescence; Eu 3+ ions 1. Introduction It has been shown [1–3] that heavy metal oxide (HMO) glassesareveryattractivehostsforrare-earth(RE)ions.In particular, PbO–Bi 2 O 3 –Ga 2 O 3 –BaO (PBG) glasses [4] are interesting because they possess high transparency (up to 60%) within the 0.6–8:7 m spectral range. The PbO and Bi 2 O 3 oxides[4,5]mainlydeterminetheiropticalproperties whilstintroductionofGa 2 O 3 givesincreasingthermostabil- ityoftheglasses[6,7].Wehavefound[4]thattheoptimal transparency of the glasses corresponds to the composi- tion: 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 parallelepipeds (8 × 8 × 1mm 3 ) as well as lm speci- mens (thickness varying 0.5–15 m) deposited on quartz substrates. Thisglasshasaglasstransitiontemperature(640K)and alargethermalexpansioncoecient(123 ×10 -7 K -1 )with a refractive index 2.154 (for the wavelength 633 nm). All ofthesefeaturesputthisglassamongthepromisingmateri- als for the manufacture of optical ber in the near-infrared (NIR) spectral range. Their wide IR transparency (up to * Corresponding author. Present address: Faculty of Science, Labora- toire de l’Etat Condense, Universite du Maine, ave Olivier Messiaen, 72085 Le Mans Cedex 09, France. E-mail address: ikityk@univ-lemans.fr (I.V. Kityk). 8:8 m) is a result of a relatively low frequency of maxi- mum of phonon energy (about 700 cm -1 ) (compared, for instance,withoxideglasses)[8].Thelatterfactorisimport- ant for creation of convenient materials for IR and vis- ible electronics and optoelectronics. More information concerning their optoelectronic properties is presented in Refs.[9–12]. The main criterion for obtaining high eciency lumi- nescence of the RE elements in glasses is for the host glass to possess low phonon energies. This occurs in the HMOglassesbecauseofthelargeatomicelements,Pband Bi. This also results in the glass having a high refractive index. In this paper, we report the observation of strong near infrared luminescence from Eu 3+ ions embedded into the PGB glasses. To the best of our knowledge, NIR lumines- cencefromEu 3+ ions,embeddedinaPGBglasshasnotyet been reported. 2. Experimental details 2.1. Specimen preparation Startingmaterialsofpurityabout99.997%weremixedto yield50gbatchesofPbO–Bi 2 O 3 –Ga 2 O 3 –BaOtakeninthe appropriate composition ratios. 99.996% purity Eu 2 O 3 was 0030-3992/01/$-see front matter c  2001 Elsevier Science Ltd. All rights reserved. PII:S0030-3992(01)00012-3