Fluoroindate Glass Co-Doped with Yb(3+)/Ho(3+) as a 2.85 μm Luminescent Source for MID-IR Sensing

This work reports on the fabrication and analysis of near-infrared and mid-infrared luminescence spectra and their decays in fluoroindate glasses co-doped with Yb(3+)/Ho(3+). The attention has been paid to the analysis of the Yb(3+) → Ho(3+) energy transfer processed ions in fluoroindate glasses pumped by 976 nm laser diode. The most effective sensitization for 2 μm luminescence has been obtained in glass co-doped with 0.8YbF(3)/1.6HoF(3). Further study in the mid-infrared spectral range (2.85 μm) showed that the maximum emission intensity has been obtained in fluoroindate glass co-doped with 0.1YbF(3)/1.4HoF(3). The obtained efficiency of Yb(3+) → Ho(3+) energy transfer was calculated to be up to 61% (0.8YbF(3)/1.6HoF(3)), which confirms the possibility of obtaining an efficient glass or glass fiber infrared source for a MID-infrared (MID-IR) sensing application.