Preparation,characterization And Applications Of Rare Earth Ions Doped AlF₃-TeO₂ Based Glass Fibers

Fluoride fibers with relative wide transmission windows and low phonon energies have applied in the development of mid-infrared lasers,broadband supercontinuum light sources,and ultraviolet/visible lasers.Among them,AlF3 based glass fibers were expected to develop mid-infrared fiber lasers with practical high output powers for their relative high glass transition temperatures and good chemical stabilities.Recently,in order to further increase the thermal stability of the AlF3 based glass,researchers developed a kind of AlF₃-TeO₂ based glass which good chemical stability and good anti-crystallization ability.However,AlF₃-TeO₂ based glass fibers have not been reported so far.The author had systematically studied on the design,fabrication of rare earth ions doped AlF₃-TeO₂ glass fibers and the developments of ²?m lasers,the obtained research results were listed as follows:?1?An AlF₃-TeO₂ based glass fiber was fabricated by using a rod-in-tube method for the first time.The matrix material had a composition of AlF3–BaF2–CaF2–YF3–SrF2–MgF2–TeO2.The fiber loss at 1560 nm wavelength was 2.3 dB/m.?2?A 1900 nm laser was obtained by using the Tm³⁺-doped AlF₃-TeO₂-based glass fibers as the gain media.In the experiments,the pump resource was a 1570 nm fiber laser,the gain fiber length was 48 cm.As the pump power increased to 891 mW,the laser output power was 314 mW,and the corresponding slope efficiency was 37.2%.?3?An efficient 2065 nm laser was achieved by using the Ho³⁺-doped AlF₃-TeO₂-based glass fibers as the gain media.In the experiments,the length of the gain fiber was 38 cm,the pump resource was a 1965 nm fiber laser.As the pump power was 325 mW,the laser output power was 82 mW,and the corresponding slope efficiency reached up to 68.8%.?4?We observed intense 2.7 ?m fluorescence in heavily Er³⁺-doped AlF₃-TeO₂-based glass fibers.The rese arch results showed that the cross-relaxation between Er³⁺ ions?4I13/2?4I15/2: 4I13/2?4I9/2?can be enhanced by adjusting the doping concentration of Er³⁺,which is beneficial for obtaining intense 2.7 ?m fluorescence.