两路光纤激光器自组织相干合成实验研究

Experimental study on coherent combining of two self-organized fiber lasers

建立了两路光纤激光器自组织相干合成的理论模型,并进行实验验证。结果表明,通过能量的相互注入,可以实现光纤激光器的自组织相干合成,合成效率达到92%。当外界基本没有干扰时,远场光斑为稳定、高对比度的干涉条纹,激光器阵列输出模式为异相模,与理论分析的结果一致;当外界环境存在轻微干扰时,实验出现条纹移动现象,输出模式也不再是恒定的异相模。对外界干扰对自组织相干合成的影响进行了数值分析,结果表明:外界干扰的幅度与频率越大,两束激光的相位差的变化幅度与频率也就越大;当外界干扰超过一定程度,两束激光之间的相位差将不能被锁定,始终处于变化状态。

Coherent combining of two self-organized fiber lasers is investigated theoretically and experimentally. It is shown that fiber lasers can be coherently combined using self-coherence by mutual injection, and the experimental combining efficiency can reach 92%. Interference fringes with high contrast ratio showing out-of -phase mode were obtained when there was little environmental interference. The experimental result is consistent with the conclusion deduced by the theoretical model. The motion of interference fringes caused by the environmental interference were also observed. The evolution of phase difference between two laser beams was calculated numerically in the case that the phase noise induced by environmental interference exists. The results show that the phase difference will change more notable and rapidly as amplitude and frequency of the phase noise get larger. The two laser beams will not be phase-locked when amplitude and frequency of the phase noise are beyond certain values.