Dy3+-doped phosphate glass optical fibers for 577 nm wavelength fiber lasers

Lasers emitting in the visible find applications in biology and medicine. Considering the success of near-infrared fiber lasers, the possibility to optically pump rare-earth-doped fibers in the blue to directly obtain visible emission is attractive. The recent progress in the field of GaN-based blue laser diodes offers new scopes. Dy3+-doped materials have received much interest because of their intense yellow emission originating from the 4F9/2→6H13/2 transition. An involvement of a glass matrix benefiting from enhanced thermo-mechanical properties would ease diode pumping. We report on the synthesis of a series of novel phosphate glasses in the system P2O5-Al2O3–BaO-K2O doped with Dy2O3. The Dy3+ concentrations were 0.05, 0.21, 0.83 and 2.5 [1020 ions/cm3]. The glasses were synthesized by the standard melt-quenching technique and thoroughly characterized in their physical, thermo-mechanical and optical properties. A Dy3+-doped optical fiber was drawn by preform drawing from the developed glasses, with the preform being obtained by rod-in tube technique, combining a cast core and an extruded cladding. Preliminary emission results in the visible from the fabricated fiber will be reported.