Enhancing excited-state lifetimes in Er³⁺-doped silica glass through controlled heat exposure

Optimization of rare-earth (RE) doped devices for laser applications necessitates a combination of precision material engineering and advanced performance enhancement strategies. This study presents a novel investigation, to our knowledge, into cluster dynamics in Er-doped glass, utilizing localized CO₂ laser heating to simulate the high-temperature conditions typical of glass fabrication processes. Our findings demonstrate that, by a controlled heat exposure, it is possible to influence clustering in Er-doped glass. Minimized clustering leads to a significant improvement in material properties and ultimately device performance. Specifically, we achieved up to 25% increase in the radiative lifetime associated with the ⁴I_13/2 → ⁴I_15/2 radiative transition by exposing samples to elevated temperatures for several minutes. This rapid thermal treatment minimizes dopant mobility in sintered silica glass, thereby reducing cluster formation and improving the homogeneity of the active medium. These results provide a feasible pathway for enhancing the performance of erbium-based optical devices, including lasers and signal amplifiers, and underscore the potential of thermal processing as a versatile tool in photonic material optimization.