High Power Tandem Pumped Ytterbium-Doped Fiber Amplifier Employing Low-NA Fiber
Year: 2025
Type: article
Abstract: The power scaling of tandem pumped ytterbium-doped fiber lasers (YDFLs) is mainly limited by the nonlinear effect such as the stimulated Raman scattering (SRS). Applying a kind of YDF featuring a large mode field area (LMA) and few guided modes is one of the effective methods to improve the SRS threshold while achieving mode control. With the benefits of small V values, few guided modes and LMA, low-numerical aperture (NA) fibers have potential for effective mode control and high SRS threshold. In this contribution, a low-NA YDF with a core/ inner cladding diameter of 40/250 μm and core NA∼0.051 is fabricated for high power tandem pumped fiber laser. Compared with the conventional YDF, the low-NA fiber amplifier reaches a maximum output power of 7.1 kW with beam quality M2∼2.3 using a forward tandem pumping scheme, providing significant advantages of improving beam quality and transverse mode instability (TMI) threshold. This work indicates the great potential of low-NA fibers applied in tandem-pumped fiber lasers for high-power laser systems requiring further power scaling and excellent beam quality, such as precision industrial machining.
Source: IEEE photonics journal
Authors: Mengfan Cui, Chongwei Wang, Haobo Li, Zhiyong Pan, Hu Xiao, Zilun Chen, Zhiping Yan, Pengfei Ma, Zefeng Wang, Jinbao Chen
Institution: National University of Defense Technology
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $2,075
OpenAlex ID: W4408254287