Energy transfer of Er3+-Nd3+ co-doped in tellurite glass via energy level match

Er³⁺/Nd³⁺ co-doped tellurate glass was prepared by melt quenching method. The relationship between the energy levels of two rare earth ions was studied by absorption spectra and excitation spectra. At 379/407/488 nm excitation, visible light, near-infrared (NIR) emission spectra, and fluorescence attenuation curves were measured. The NIR emission spectrum and fluorescence lifetime show that Er³⁺ can transfer energy to Nd³⁺, thus enhancing the NIR emission of Nd³⁺ in tellurate glass. In the co-doped sample, under excitation of 379/407/488 nm, the NIR emission of Nd³⁺ has a concentration quenching point related to Er³⁺, and the optimal co-doped concentration is 1mol% ErF₃. At 365/451 nm excitation, NIR emission was not enhanced and no energy transfer occurred. In contrast to the energy transfer between conventional Er³⁺-Nd³⁺ co-doped glasses, this paper investigates the effect of matching the higher Er³⁺ energy levels with adjacent Nd³⁺ levels on the energy transfer. The energy transfer process of Er³⁺-Nd³⁺ co-doped glasses is studied in the energy level diagram.