Photolμminescence properties of gypsμm

摘要

The photolμminescence (PL) properties of four gypsμms from three localities, namely, Inner Mongolia (China), Turkey, and Canada, are investigated at room temperature. Under 365-nm excitation, two types of gypsμms from Inner Mongolia exhibit different lμminescence colors, namely, yellow and cyan-white, and gypsμms from Turkey and Canada exhibit yellow and bluish-white lμminescence, respectively. The PL spectra of these gypsμms consist of continuous sub-bands distributed in all visible wavelengths, and the excitation spectra of these gypsμms consist of continuous sub-bands distributed in a wide range of wavelengths, i.e., 200-500 nm. The features of PL and excitation spectra suggest that the origin of lμminescence from these gypsμms may be lμminescent organic substances included into crystals in the growth process rather than the impurity ions substituted for Ca~(2+).