Chamorovskiy A, Rautiainen J, Rantamäki A, Golant K M, Okhotnikov O G
Optoelectronics Research Centre, Tampere University of Technology, Tampere, Finland.
Opt Express. 2011 Mar 28;19(7):6433-8. doi: 10.1364/OE.19.006433.
A hybrid Raman-bismuth fiber amplifier pumped in co-propagation configuration by a single 1.22 µm semiconductor disk laser is presented. The unique attribute of this dual-gain system is that both amplifiers require the pump source with the same wavelength because pump-Stokes spectral shift in 1.3 µm Raman amplifier and pump-gain bandwidth separation in 1.3 µm bismuth fiber amplifier have the same value. Residual pump power at the output of Raman amplifier in this scheme is efficiently consumed by bismuth-doped fiber thus increasing the overall conversion efficiency. The small-signal gain of 18 dB at 1.3 W of pump power has been achieved for hybrid scheme which is by 9 dB higher as compared with isolated Raman amplifier without bismuth fiber. Low noise performance of pump semiconductor disk laser with RIN of -150 dB/Hz combined with nearly diffraction-limited beam quality and Watt-level output powers allows for efficient core-pumping of a single-mode fiber amplifier systems and opens up new opportunities for amplification in O-band spectral range.
介绍了一种采用单台1.22μm半导体盘激光器同向泵浦配置的混合拉曼 - 铋光纤放大器。这种双增益系统的独特之处在于，两个放大器都需要相同波长的泵浦源，因为1.3μm拉曼放大器中的泵浦 - 斯托克斯光谱位移与1.3μm铋光纤放大器中的泵浦 - 增益带宽分离具有相同的值。在该方案中，拉曼放大器输出端的残余泵浦功率被掺铋光纤有效消耗，从而提高了整体转换效率。混合方案在1.3W泵浦功率下实现了18dB的小信号增益，与没有铋光纤的孤立拉曼放大器相比，高出9dB。泵浦半导体盘激光器具有-150dB/Hz的RIN、接近衍射极限的光束质量和瓦级输出功率，其低噪声性能允许对单模光纤放大器系统进行高效的纤芯泵浦，并为O波段光谱范围内的放大开辟了新机会。
