Experiment research of Nd:YLF laser amplifier tightly ring-pumped by high power LD array

The 5mm×5mm laser pulse is amplified using 10mm×10mm Nd:YLF laser amplifier tightly ring-pumped by high power LDA and two-stage double-pass abaxial travelling wave amplifying structure. The rules of gain of laser amplifier and amplifying system with pump current and pump delay are studied by simulation and experiment. The two-stage double-pass abaxial small-signal net gain of amplifying system is 600 in experiment, and the energy extract efficiency is 0.86%. The results of experiment and simulation indicate that the structure of the amplifier and amplifying system has high energy extract efficiency and gain, low coupling loss, the advantages of being compact and simple and so on.