Energy transfer and frequency upconversion in Yb3+–Er3+-doped PbO-GeO2 glass containing silver nanoparticles

Abstract

We report the infrared-to-visible frequency up- conversion in Er 3+ -Yb 3+ -codoped PbO-GeO2 glass con- taining silver nanoparticles (NPs). The optical excitation is made with a laser at 980 nm in resonance with the 2 F5/2 → 2 F7/2 transition of Yb 3+ ions. Intense emission bands cen- tered at 525, 550, and 662 nm were observed correspond- ing to Er 3+ transitions. The simultaneous influence of the Yb 3+ → Er 3+ energy transfer and the contribution of the in- tensified local field effect due to the silver NPs give origin to the enhancement of the whole frequency upconversion spec- tra.