国产泵浦增益一体化复合功能激光光纤实现8.74 kW激光输出

正高功率光纤激光器一般采用信号光与MOPA放大级的"1+1"型串联结构,而第二级的MOPA放大结构通常存在两种结构方式:其一是短距离集中式端面泵浦方式,包括正向端泵和反向端泵,后者具有一定的技术优势,有利于实现窄线宽激光输出;其二是长距离分布式侧面泵浦方式,其工作原理是基于倏逝波耦合效应来实现数十米长度的长程侧面耦合,其典型代表是泵浦增益一体化复合功能激光光纤(又被称为"GT-wave光

8.74 kW (8+1) GT-wave fiber amplifier

A new-type of (8+1) GT-wave fiber was fabricated by our newly-optimized specialty fiber assembly and coating techniques for the first time. This (8+1) GT-wave fiber allowed for 10.66 kW aggregated pump power at 976 nm from 6 counter-pump-ports in a master oscillator power amplifier (MOPA) laser setup and stably presented 8.72 kW laser output at 1 079.4 nm with a high optical-to-optical efficiency of 81.0%. This is the highest power of the fiber amplifiers pumped by commercial laser diodes that has been reported so far, and only limited by the available pump power. Up to this power level, pure output spectrum with narrow 3 dB bandwidth Δλ_{3 dB} of 2.76 nm and without any sign of stimulated Raman scattering and amplified spontaneous emission was obtained. With other ten pump-ports to collect more pump power, a further power scaling towards 10 kW or above can be expected.