Radioluminescent mechanism of Li2B4O7:Cu crystal

The structure of the radioluminescent (RL) spectrum of Li2B4O7:Cu crystal is complex, having no normal Gauss peaks. The RL spectrum recorded showed one sharp and strong peak near 365 nm. For the purpose of explaining this phenomenon, we used the self-trapped exciton (STE) model to analyze experimental data of absorption spectrum, emission spectrum, radioluminescence spectrum and decay-time curves. We found a short lifetime component (of the order of ns) from phosphorous signals of Li2B4O7:Cu. We realized that the short lifetime component related to inherent signal of host lattice and the d-p transitions of Cu+. This result is applicable in the detector system with high time resolution.