AUTHOR=Yang Xuezong , Bai Zhenxu , Jiang Huawei , Mildren Richard P. , Feng Yan TITLE=A Narrow-Linewidth Linearly Polarized 1018-nm Fiber Source for Pumping Diamond Raman Laser JOURNAL=Frontiers in Physics VOLUME=9 YEAR=2021 URL=https://www.frontiersin.org/journals/physics/articles/10.3389/fphy.2021.727109 DOI=10.3389/fphy.2021.727109 ISSN=2296-424X ABSTRACT=

A 7.8-GHz linewidth ytterbium-doped fiber (YDF) laser with an output power of 75 W at 1,018 nm is demonstrated based on narrow-bandwidth fiber Bragg gratings. Effective suppression of spectral broadening and amplified spontaneous emission is achieved by optimizing the resonator structure and active fiber parameters. An 1,178-nm diamond Raman output pumped by this narrow-linewidth 1,018 nm source is addressed in this study, which shows a promising application of generating the sodium guide star laser at 589 nm. A single-longitudinal-mode Stokes with an output power of 0.6 W is obtained using this multimode 1,018 nm laser at the pump power of 13 W. The impact of pump spectral linewidth on the effective Raman gain coefficient is analyzed, and the laser threshold of the diamond Stokes resonator increases with the broadening of the pump linewidth.