1.63kW单纤单振单模连续全光纤激光器

1.63kW monolithic continuous-wave single-mode fiber laser oscillator

报道了一种单纤单振单模连续全光纤激光器,工作波长为1 080nm,输出功率可达1.63kW。激光器使用7个输出功率为300 W、工作波长为976nm的半导体激光器(LDs)充当泵浦源,并利用短腔长结构成功地抑制了受激拉曼散射(SRS)。测试结果显示,所获得激光的光谱信噪比(SNR)大于40dB,1h内的功率不稳定度小于1%,光-光转换效率约为75.46%。此外,通过对光纤盘绕的合理设计,有效地抑制了光纤中的高阶模式,在满功率输出时成功地获得了单模激光(M2<1.1)。

We demonstrate a monolithic continuous wave （CW） fiber laser oscillator, producing ~ 1.63 kW laser power at 1080 nm. In our experiment,the monolithic laser oscillator was pumped by 7 fiber- pigtailed laser diodes with the maximum output power of ~ 300 W. The operating wavelengths of all these pump laser diodes are near 976 urn,enabling a short laser cavity （~27 m） to effectively suppress the stimulated Raman scattering （SRS）. The laser spectrum with the maximum output power has a sig- nal to noise ratio （SNR） more than 40 dB. In addition, the fiber coiling technique was adopted to effec- tively depress the high-order laser modes to obtain the single mode beam quality （M2〈1. 1） at the max- imum output laser power. The optical to optical conversion efficiency of the monolithic laser oscillator with respect to the launched pump power is as high as ~75.46%. The laser oscillator kept running for an hour at the maximum output power. No power roll-over was observed and power fluctuation lower than 1 % was achieved. The all fiber construction of the laser oscillator enables compact size, mainte- nance-free,robust operation and thus allows various practical applications in industry material process- ing, such as laser cutting, laser drilling, laser clamping, laser welding, etc.