Enhanced broadband near-infrared luminescence and its origin in Yb/Bi co-doped borophosphate glasses and fibers

摘要

Yb/Bi co-doped borophosphate glasses and fibers were prepared. The effect of Yb~(3 +) on the near-infrared (NIR) luminescent properties and the mechanism of luminescence of Bi-ions were investigated. Under 976 nm laser diode (LD) excitation, the NIR emission intensity of the glass with 8 mol% Yb_2O_3 co-doped glass is ~37 times stronger than that of Bi singly-doped glass. The fluorescence lifetime increases by ~ 7 times with 5 mol% Yb_2O_3 co-doped glass. The energy transfer efficiency is ~ 59.1%. It is also suggested that the broadband NIR luminescence pumped by 808 nm and 976 nm LDs derives from Bi~+ and Bi~(2 +), respectively.