Switchable-multi-wavelength fiber laser based on dual-core all-solid photonic bandgap fiber

In this paper, we propose and demonstrate a switchable multi-wavelength fiber laser based on a dual-core all-solid photonic bandgap fiber (PBGF) comb-like filter. The transmission properties of the dual-core all-solid PBGF are theoretically and experimentally investigated. Then the fiber ring laser based on the PBGF is realized and its wavelength-selective mechanisms are studied. By adjusting the polarization controller (PC), the number and location of the laser wavelength can be tunable.     

Eyesafe high peak power pulsed fiber lasers limited by fiber nonlinearity

We present design and performances of several eye-safe high peak power fiber lasers operating either around 1550 nm or 2000 nm. They share the limitations by nonlinear effects either Stimulated Brillouin Scattering for single frequency lasers or Kerr related effects for short pulse amplifiers. Performances above 1 kW peak power for single frequency lasers and 26 nJ for short pulse fiber lasers are reported. The influence of the saturation power of the fibers on the non-linearity is discussed and applied to a comparison between Erbium and Ytterbium co-doped fibers and Thulium doped fibers. The Brillouin gain properties in these fibers are also compared.     

高功率光纤激光信号耦合器

实验研究了由三根信号光纤锥形束和一根多模光纤组成的3×1信号耦合器.通过仿真,发现锥形长度越长传输效率和输出光束质量越好,同时也验证了对于低阶模场的吸收要高于高阶模场.实验中,制作了锥区长度为10 mm的3×1信号耦合器,在单纤注入信号功率分别为258 W和365 W的情况下获得转换效率为96.6%的信号输出,总输出功率602W,光束质量为Mx2 = 10.5, My2 = 9.7.     

高功率脉冲双包层光纤激光器的新进展

对高功率脉冲双包层光纤激光器的国内外研究进展进行评述,通过建立了小信号瞬态增益模型,对脉冲激光信号经过双包层光纤放大后的波形进行了数值模拟.分析了基于MOPA方式脉冲双包层光纤激光器的几个问题,报道了中科院上海光机所采用振荡-放大(MOPA)方法获得133.8 W平均功率脉冲放大输出的实验结果.     

高功率Er/Yb共掺光纤超荧光光源

为了获得高功率超荧光输出,采用6个976nm的LD,通过一个光纤束耦合器同时抽运Er/Yb共掺光纤,分别研究了单程后向结构和双程后向结构超荧光光源的输出特性.采用单程后向装置,当抽运功率为957mW时,输出功率为120.4mW,斜率效率达到17.5%.在双程后向结构的实验装置中加入4m掺Er光纤,有效地将超荧光的3dB带宽拓展到88nm.     

W-type fiber design for application in U- and S-band amplifiers by controlling the LP01 mode long wavelength cut-off

We propose a novel passive band-pass filtering scheme to obtain a net gain in a band-competing system using a W-type fiber waveguide, slicing a shorter wavelength gain band out of a given stimulated emission cross-section. By controlling the location of the LP₀₁ mode cut-off, fiber design parameters are presented for obtaining a U-band gain from Tm ions and S-band from Er ions. The tolerance of the LP₀₁ mode cut-off wavelength and the accompanying bending loss are theoretically analyzed in terms of waveguide parameters.     

光纤损耗和自发辐射对掺镱双包层光纤激光器的影响

本文主要从速率方程出发,分析了光纤损耗和自发辐射对线形腔掺镱双包层光纤激光器的影响.通过数值模拟,结果表明光纤损耗对激光阈值、激光增益、输出功率都有影响,而自发辐射主要对激光输出功率产生一定的影响.从而为光纤激光器的优化设计提供理论依据.