Nd3+-doped silica glass and fiber prepared by modified sol-gel method

Yinggang Chen; Zhiquan Lin; Yafei Wang; Meng Wang; Lei Zhang; Yan Jiao; Hehe Dong; Shikai Wang; Chunlei Yu; Lili Hu

doi:10.3788/COL202220.091601

Abstract

Large-size

{Al}^{3 +} / {Nd}^{3 +}

co-doped silica glass with 5000 ppm

{Nd}^{3 +}

and 50,000 ppm

{Al}^{3 +}

doping concentrations was prepared by the modified sol-gel method combined with high-temperature melting and molding technology. Electron probe micro-analyzer tests indicated that high doping homogeneity was achieved with this sample preparation method. The spectral properties of the

{Nd}^{3 +}

ions were evaluated.

{Nd}^{3 +}

-doped silica fiber (NDF) with a core-to-clad ratio of 20/125 μm was drawn from the preform with the

{Al}^{3 +} / {Nd}^{3 +}

co-doped silica glass as the core. In the laser oscillation experiment, a maximum output power of 14.6 W at 1.06 μm with a slope efficiency of 39.6% was obtained from the NDF pumped by a commercial 808 nm laser diode. To the best of our knowledge, this is the highest laser power reported for an NDF operated at 1060 nm and prepared by a non-chemical vapor deposition method. In the master oscillator power amplifier experiment, a maximum power of 16.6 W corresponding to a slope efficiency of 30.5% at 1061 nm was also demonstrated. The laser performance of the NDF exhibited the great advantages and potential of the modified sol-gel method in fabricating

{Nd}^{3 +}

-doped silica glass for a new type of NDFs like large mode area fibers and fibers with large diameter ratio of core/cladding.