Dy3+ doped sodium–magnesium–aluminum–phosphate glasses for greenish–yellow waveguide light sources

Abstract Intense greenish–yellow emission near the hemoglobin absorption peak at 577 nm was observed in Dy 3 + doped sodium–magnesium–aluminum–phosphate (NMAP) glasses under UV excitation. The Judd–Ofelt intensity parameters and the integrated fluorescence intensity ratio between 4 F 9/2 → 6 H 13/2 (yellow) and 4 F 9/2 → 6 H 15/2 (blue) imply a strong asymmetrical and covalent environment around Dy 3 + in the phosphate glasses. The fluorescence branching ratio and the stimulated emission cross-section of the 4 F 9/2 → 6 H 13/2 transition were identified to be 65.9% and 25.65 × 10 − 22 cm 2 , respectively, confirming the efficiency of the visible fluorescence emission. Channel waveguide was fabricated successfully by K + –Na + ion-exchange method with mode field diameter of 20.5 μm in the horizontal direction and 8.7 μm in the vertical direction. The results demonstrate that Dy 3 + doped NMAP glasses are promising to develop waveguide light sources for thrombolysis.