The comparative study of high efficiency of Tm^{3+}-doped fiber laser at 1.72 μm for different pump schemes

Abstract: In this study, we revealed the impact of the pumping scheme, fiber length, pumping power, and reflectivity of the output fiber Bragg grating on the performance of a Tm^3+ -doped fiber laser (TDFL) operating at a wavelength of 1.72 \mu m. Using numerical simulations, we optimized the output power and reduced losses due to reabsorption; as well as amplified spontaneous emission (ASE) at approximately 1820 nm. The Tm^3+ -doped fiber was bi-directionally pumped at 1570 nm to enhance the pump absorption. The simulations suggest that a maximum power of 5.96W at 1.72 \mu m and a slope efficiency of 64 % are achievable using a Tm^{3+}-doped silica fiber with a bi-directional pump of 4 W forward and 6 W backward.