Radiation Physics and Chemistry 67 (2003) 587–591 UV and electron radiation-induced luminescence of Cu- and Eu-doped lithium tetraborates M. Ignatovych a, *, V. Holovey b , A. Watterich c , T. Vid ! oczy d , P. Baranyai d , A. Kelemen e , V. Ogenko a , O. Chuiko a a Institute of Surface Chemistry, NASU, 17 Gen. Naumov Str., Kyiv 03164, Ukraine b Institute of Electronic Physics, NASU, 21 University Str., Uzhgorod 88000, Ukraine c Institute of Solid State Physics and Optics, HAS, P.O.Box 49, Budapest, 1525 Hungary d Photoscience Laboratory, BUTE and HAS CRC, P.O. Box 17, Budapest 1525, Hungary e Institute for Isotope and Surface Chemistry, HAS CRC, P.O. Box 77, Budapest 1525, Hungary Abstract Cu- and Eu-doped Li 2 B 4 O 7 has been characterized using steady-state and time-resolved photoluminescence, radioluminescence and optical absorption techniques. The effect of dopant content (7.0 Â 10 À4 –5.0 Â 10 À2 wt% for Cu and 1.6 Â 10 À3 –8.0 Â 10 À3 wt% for Eu) and of host modification (single crystal, polycrystalline and glassy) has been investigated. r 2003 Elsevier Science Ltd. All rights reserved. Keywords: Photoluminescence; Radioluminescence; Cu- and Eu-doped lithium tetraborate 1. Introduction Cu- and Eu-doped borates exhibit very promising characteristics as laser hosts, scintillators and tissue- equivalent thermoluminescent (TL) detectors. In all these applications the doped borates interact with different kinds of radiation, and their luminescent properties are strongly determined by the nature of dopant as well as by the host–matrix state. Thus, fundamental spectral characterization of these advanced materials is of understandable importance. Until now most publications are devoted to TL characterization of these materials, while photoluminescence (PhL) and radioluminescence (RL) studies are quite limited and mainly concern LTB:Cu (Furetta, 2001). As to trivalent rare-earth metal-doped Li 2 B 4 O 7 (LTB) and LTB:Eu 3+ , in particular, data are even more scarce, which is connected to the known difficulties to introduce the large Eu 3+ in the LTB single crystal. Recently, Dubovik (2000) has successfully grown LTB:Eu 3+ single crystal, and reported that its PhL spectrum was practically the same as that of LTB:Eu glassy sample. To the best of our knowledge time-resolved PhL and RL studies on these materials are reported for the first time. This paper is an attempt to start systematic PhL and RL studies on Cu- and Eu-doped LTB using various dopant contents and host modifications: single crystal, polycrystalline, glassy. 2. Experimental 2.1. Materials Single crystals of LTB:Eu and LTB:Cu were grown by the Chochralski method. A special approach has been adopted to obtain the same dopant content for all three modifications. The dopant content in the sample was measured by atomic absorption spectroscopy for Cu and by neutron activation analysis for Eu. *Corresponding author. 0969-806X/03/$ - see front matter r 2003 Elsevier Science Ltd. All rights reserved. doi:10.1016/S0969-806X(03)00110-5