Abstract
Enhancing the luminescence characteristics of rare earth doped borate glasses is the key issue in achieving an accurate dosimeter. Series of lithium and magnesium oxide modified borate glasses of compositions 20Li(2)O-(70-x)B2O3-10MgO-xDy(2)O(3), where 0.3 <= x <= 1 mol% are prepared using melt-quenching method. Synthesized samples are further activated with different concentration of Dy3+ and subjected to different doses by using a Co-60 source. Effects of Dy3+ concentrations on luminescence behavior are examined. XRD patterns confirm the amorphous nature of all samples. A simple glow curve exhibits a peak at 190 degrees C and optimum intensity for 0.5 mol% of Dy3+ ions. Thermoluminescence (TL) properties including dose response and effective atomic number are determined. A good linearity in the dose response with correlation coefficient similar to 0.9977 and a tissue equivalent Z(eff)similar to 8.71 is achieved. The room temperature photoluminescence (PL) spectra of these glasses under 350 nm laser excitations reveal two enhanced peaks centered at 480 nm (blue) and 573 nm (yellow). The mechanism for the TL and PL enhancements are discussed and understood. These attractive luminescence features of prepared glasses may contribute towards the advancement of dosimetry. (C) 2015 Elsevier Ltd. All rights reserved.