Laser operation at 1.2 µm in Ho³⁺-doped ZBYA glass fibers

Abstract

Powerful 1.2-µm laser operation was produced in Ho3+-doped single-cladding, in-house fabricated ZrF4-BaF2-YF3-AlF3 (ZBYA) glass fibers. The fibers were fabricated based on ZBYA glass with a composition of ZrF4-BaF2-YF3-AlF3. Pumped by an 1150-nm Raman fiber laser, the maximum combined laser output power emitted from both sides of a 0.5-mol% Ho3+-doped ZBYA fiber was 6.7 W, with a slope efficiency of 40.5%. We also observed lasing at 2.9 µm with an output power of 350 mW, which was ascribed to the transition of Ho3+:5I6 → 5I7. The effect of rare earth (RE) doping concentration and the length of the gain fiber were also investigated to determine their effect on laser performance at 1.2 µm and 2.9 µm.

High power tunable Raman fiber laser at 1.2 μm waveband

“…Currently, fiber lasers operating at 1.2 μm waveband can be divided into two groups in terms of the lasing mechanism. The first one adopts some special ion-doped fibers such as bismuth-doped fiber or holmium-doped fluoride fiber to provide optical gain at this waveband directly [ 17 – 19 ]. However, due to the relatively small gain coefficient and difficulties in the fiber fabrication process, the output power of these lasers at 1.2 μm waveband is limited within ten-watt level [ 18 , 19 ].…”

“…The first one adopts some special ion-doped fibers such as bismuth-doped fiber or holmium-doped fluoride fiber to provide optical gain at this waveband directly [ 17 – 19 ]. However, due to the relatively small gain coefficient and difficulties in the fiber fabrication process, the output power of these lasers at 1.2 μm waveband is limited within ten-watt level [ 18 , 19 ]. The other one utilizes stimulated Raman scattering effect in passive fiber to convert the beam from a high power ytterbium-doped fiber laser (YDFL) into 1.2 μm waveband [ 20 – 23 ].…”