Effect of OH− on upconversion luminescence of Er3+-doped oxyhalide tellurite glasses

The Raman spectra, infrared spectra and upconversion luminescence spectra were studied, and the effect mechanism of OH− groups on the upconversion luminescence of Er3+-doped oxyhalide tellurite glasses was analyzed. The results show that the phonon energy of lead chloride tellurite (PCT) glass was lower than that of lead fluoride tellurite (PFT) glass, but upconversion luminescence intensity of Er3+-doped PFT glass was higher than that of Er3+-doped PCT glass. The analysis considers that it was attributed mainly to the effect of OH− groups. The lower the absorption coefficient of the OH− groups, the higher the fluorescence lifetime of Er3+, and as a result the higher upconversion luminescence intensity of Er3+. In this work, the effect of OH− groups on the upconversion luminescence of Er3+ was bigger than that of the phonon energy.