Thermally stimulated luminescence from alkaline earth borates

The thermally stimulated luminescence from XB2O4 (X=Ca,Sr,Ba) has been investigated. The results on CaB2O4 and SrB2O4 are being reported here for the first time. In both cases, the emission is found to be quite intense, contrary to the case with BaB2O4. The presence of two peaks in the glow curves is noted over the temperature range of 300–570 K. The emission spectra corresponding to both the peaks have been observed to be identical, consisting of two broad emissions, one in the UV and other in the blue–green regions. The emission is apparently quite different from that of BaB2O4 in which case only very weak emission spreading over a broad wavelength range around 410 nm is observed. This result has been understood in terms of the overlap between the excitation and the emission spectra.