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

•Intense greenish–yellow emission is observed in Dy3 + doped phosphate glasses.•High asymmetrical and covalent environment is identified in the glass system.•Glass waveguides have been fabricated by K+–Na+ ion-exchange method.•Waveguide light sources near 577 nm are promisingly employed in thrombolysis.

Intense greenish–yellow emission near the hemoglobin absorption peak at 577 nm was observed in Dy3 + doped sodium–magnesium–aluminum–phosphate (NMAP) glasses under UV excitation. The Judd–Ofelt intensity parameters and the integrated fluorescence intensity ratio between 4F9/2 → 6H13/2 (yellow) and 4F9/2 → 6H15/2 (blue) imply a strong asymmetrical and covalent environment around Dy3 + in the phosphate glasses. The fluorescence branching ratio and the stimulated emission cross-section of the 4F9/2 → 6H13/2 transition were identified to be 65.9% and 25.65 × 10− 22 cm2, 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 Dy3 + doped NMAP glasses are promising to develop waveguide light sources for thrombolysis.