Crystal growth study of CaGa2S4 co-doped with Ce3+ and Na+

We have examined the effects of co-doping of Ce3+ and Na+ in CaGa2S4. Differential thermal analysis and X-ray diffraction analysis were carried out on the compounds of Ca(1-x)Cex/2Nax/2Ga2S4 (0 <= x <= 1) to obtain the necessary information for their synthesis. It is shown that Ce-3+ and Na+ can be simultaneously doped into CaGa2S4 UP to about 30mol% (x = 0.6). The melting point was determined as a function of x. Photoluminescence (PL) was measured with these products, where the maximum intensity was found at 10 mol% (x = 0.2). Single crystals of Ca(1-x)Cex/2Nax/2Ga2S4 (x = 0.02 and 0.2) were grown from melt by the horizontal Bridgman method. Light absorption was measured near the fundamental absorption edge using a high quality part of the single crystals Photoluminescence excitation (PLE) spectra were also measured using compounds of Ca(1-x)Cex/2Nax/2Ga2S4 with x = 0.02 and 0.2 and 0.5 and a Ce only-doped Ca2GaS4:Ce+ (0.8 mol%). (C) 2007 Elsevier Ltd. All rights reserved.