Synergistic Enhancement of Dual-Band Stimulated Emission Cross-Sections in Nd-Doped Silica Glass via Effective Linewidth Narrowing by Phosphorus-Iodine Co-Doping

However, its 0.9 μ m emission (4F3/2 → 4I9/2) is a quasi three-level transition, which is strongly competitive with the 1.06 μ m four level transition (4F3/2 → 4I11/2); At the same time, the non-uniform broadening of the glass matrix leads to the effective linewidth of the two emission lines being too wide, which seriously restricts the improvement of its stimulated emission cross-section.

This article proposes a strategy of using P-I co doping to regulate the local coordination environment of Nd3+. By changing the crystal field symmetry and coordination intensity, the effective linewidth of the emission spectrum can be narrowed. The results showed that P-I co doping narrowed the effective linewidths of the emission spectra in the 0.9 μ m and 1.06 μ m bands by about 20 nm.