Fiber coupler for mode selection and high-efficiency pump coupling

作者:Xiao, Qirong; Chen, Xiao; Ren, Haichui; Yan, Ping; Gong, Mali*
来源:Optics Letters, 2013, 38(7): 1170-1172.
DOI:10.1364/OL.38.001170

摘要

A pump/signal fiber coupler with functions of pump light coupling and high-order-mode suppression is reported. This coupler is composed of pump fibers and a double-clad fiber (DCF) with high pump-coupling efficiency. The core of DCF is microdeformed in the coupling region, which serves mode selection. Theoretical analysis and experimental results verify these functions. In the experiment, the pump-coupling and signal-transmitting efficiency of the coupler were similar to 98% and similar to 96%, respectively. This coupler can prevent mode distortion with fundamental mode launching, and improve the fiber laser beam quality with high-order-mode launching.