Fig. 1. Simulation results of laser pulse characteristics of oscillating stage

Fig. 2. Reflectivity of the optimal output mirror versus z

Fig. 3. Output laser energy versus z

Fig. 4. Simulation results of laser pulse intensity changing with time in single pass amplification

Fig. 5. Experimental device of the oscillation stage

Fig. 6. Output energy versus LD pump energy (inset:2D beam intensity profile at maximum output energy)

Fig. 7. Output laser single pulse waveform

Fig. 8. Experimental device of amplification stage

Fig. 9. Output energy of amplifiers versus LD pump energy. (a) First stage double pass amplification; (b) second stage single pass amplification (inset: 2D beam intensity distribution of output laser at maximum output energy)

Fig. 10. Single pulse waveform of the output laser