Structure and luminescent property of Er3 +-doped germanate glasses

The structures and optical properties of GeO2–Li2O–Er2O3 glasses are investigated. The results indicate that the phonon energy of Er3 +-doped germanate glasses is decreases with the increasing in Li2O content, but the upconversion and near infrared luminescence intensity is decreases. The analysis considers that it is attributed mainly to the effect of OH− group (about 3100–3500 cm− 1) on the upconversion luminescence of Er3 + was bigger than that of the phonon energy, and also the OH− group strongly influence the NIR luminescence.