Broadband near-infrared luminescence and energy transfer in Bi singly-doped and Bi/Yb co-doped titanate glasses

Abstract:

Super-broadband near-infrared (NIR) emission from 1100 nm to 1600 nm is observed in Bi-doped titanate glasses at the excitation of 808 nm laser diode (LD). The effects of Bi content on the optical spectra are investigated. It is also found that the Bi-related emission intensity can be enhanced by Yb³⁺ co-doping at the excitation of 980 nm LD. It should be ascribed to the energy transfer from Yb³⁺ to active Bi ions. The energy transfer processes are studied based on the Inokuti-Hirayama (I-H) model, and the energy transfer of electric dipole-dipole interaction is confirmed to be dominant in Bi/Yb co-doped glasses.