Effect of silver nanoparticles on the upconversion and near-infrared emissions of Er3+:Yb3+ co-doped zinc tellurite glasses

The effect of the silver nanoparticles on the optical response of the Er3+/Yb3+ co-doped zinc tellurite glasses was studied. The glasses were characterized by optical absorption spectroscopy, transmission electron microscopy and X-ray diffractometry. The characteristic radiative emissions of Er3+ ions at visible (upconversion) and near-infrared spectral regions were recorded by exciting the samples at 980 nm excitation wavelength. The intensities of upconversion and near-infrared emissions were enhanced up to 180% and 130%, respectively. The increase in luminescence intensity is attributed to the enhanced effective localized field induced by silver nanoparticles. Lifetime measurements were conducted to investigate the presence of energy transfer between Er3+ and silver.