Cascaded combiners for a high power CW fiber laser

Abstract

We report cascaded combiners for a high power continuous wave (CW) fiber laser in this paper. The cascaded combiners are fabricated with an improved lateral splicing process. During the fusing process, there is no stress or tension between the pump fiber and the double-cladding fiber. Thus, the parameters of the combiner are better than those that have been reported. The coupling efficiency is 98.5%, and the signal insertion loss is 1%. The coupling efficiency of the cascaded combiners is 97.5%. The pump lights are individually coupled into the double-cladding fiber via five combiners. The thermal effects cannot cause damage to the combiners and the cascaded combiners can operate stably in high power CW fiber lasers. We also develop a high power CW fiber laser that generates a maximum 780 W of CW signal power at 1080 nm with 71% optical-to-optical conversion efficiency. The fiber laser is pumped via five intra-cavity cascaded combiners and five extra-cavity cascaded combiners with a maximum pump power of 1096 W and a pump wavelength of 975 nm.

Optimization of seed power for suppression of stimulated Raman scatting in all-fiber amplifiers

“…Highpower fiber lasers have great potential for development in laser welding and cutting due to their characteristics of high energy density and short wavelength [5][6][7]. However, all-fiber lasers attract more attention for industrial applications due to their advantages of ease of use and manufacture [2,[8][9][10][11][12][13][14]. Therefore, the power scaling of all-fiber lasers has become a focus of laser research during the last decade.…”

Fabrication of side pump combiners when pumping with a laser diode and a fiber laser

“…After optimization, the maximum coupled power from one pump port was about 600 W with the coupling efficiency of about 98.6%. Further, In 2016, Tan et al reported a multi-point side pump structure using five 1 1 × 1 side pumping combiners to construct a bidirectionally pumping fiber laser oscillator, each of which is coupled with 150 W pump power [15] . Later, Dong et al applied this multi-point pumped structure directly in the Yb-doped gain fiber.…”

Asymmetric taper scrambler for improved pump homogeneity and absorption in side-pumped double-clad fibre lasers

“…Additionally, pump absorption efficiency depends also on the coupling method, being possible to launch pump light through the fiber ends [4] or from the side through the cladding [5,6]. In this respect, side coupling is worthwhile, mainly due to the ends of the active fiber are free to join with other fiber components, and the pump coupling can be distributed along the fiber to improve the heat management [7,8]. Nevertheless, as the light is coupled from the side, there is a tendency of the light to propagate as a ring mode [9].…”