Mutual injection locking of two individual fiber lasers
两个光纤激光器的互相注入锁定

Coherent beam combination of fiber laser array is an important technology in realizing high power fiber laser systems. Mutual injection locking of two fiber lasers was achieved by a fiber coupling apparatus. Through experiments, we conclude that in the free running state the beam profile is the simple intensity superposition as expected of two incoherent beams, but in the mutual injection locking, interference fringes with high contrast ratio was obtained, showing good mutual coherence between two laser beams. Through the interference fringes, we concluded that the two lasers are always in the out-of-phase mode, as predicted by theory.