1018nm Short wavelength Yb3+-doped fiber laser can be widely used for tandem-pumped fiber laser system in 1 μm regime because of its high brightness, high beam quality and low quantum defect (QD). In order to achieve 1018nm short wavelength Yb3+-doped fiber laser or amplifier with high output power and high beam quality, a steady-state rate equations model considering the mode competition, bend loss has been established. We theoretically analyzed the mode competition in 1018nm short wavelength Yb3+-doped fiber laser and amplifier and the simulation results show that the when the bend radius is 5cm, the LP01 mode output power is higher than the other mode power in the fiber laser and amplifier. When the bend radius is larger than 5cm, the beam quality will decrease in fiber laser and amplifier especially for fiber laser, besides we calculated the mode power in the fiber amplifier at different power of seed laser, when the LP01 mode power is higher than the other, the beam quality will increase. At last we analyzed the evolution of transverse gain of every mode along the radial coordinate in fiber laser and amplifier. Our results can provide instructive suggestions when designing bend radius and the power of seed laser based fiber laser and amplifiers and can help to enhance the beam quality.

Date Published: 12 December 2018
PDF: 8 pages
Proc. SPIE 10844, Advanced Laser Technology and Applications, 1084406 (12 December 2018);

Published in SPIE Proceedings Vol. 10844:
Advanced Laser Technology and Applications
Shibin Jiang; Lijun Wang; Zejin Liu; Wei Shi; Pu Zhou, Editor(s)