Investigation On Efficient Amplification Of Laser Pulses In Hundred-picosecond

For nanosecond Master Oscillator-Power Amplification (MOPA) technology,femtosecond Chirped Pulse Amplification (CPA) technique and Brillouin Amplification(SBA) technology has been applied to the corresponding "Fusion Ignition" programs.With the proposing of "Impact Ignition", faced with the difficulties such as the B-integral is limited, low energy magnification, higher cost etc. to the required hundred-picosecond pulse, and therefore to get the more applicable hundred-picosecondamplification technology becomes very urgent. Due to the huge investment, thesimulation and analysis of the amplification become particularly important.Papers in hundred-picosecond use the pulse peak power magnification, energyextraction rate, pulse width, energy extraction rate, the peak B-integral and pulsewaveform as the regular indicators for the characterization of pulse amplification,explored and researched the amplification technology by numerical simulation.First, according to the mechanism of MOPA, CPA and SBS, chose the theoreticalmodels which applies in hundred-picosecond, and obtained the corresponding numericalcalculation models.Secondly, for MOPA, get the pulse waveform changes in small signal amplificationand saturation amplification and analysis the reasons. Contrary to the influence oftransmission distance and small signal gain coefficient, simulated the pulse transmissionamplification at different power density, and obtained the corresponding regular patternfor amplification and the basis for the selection of parameters. For CPA, researched theinfluence of nonlinear effects (self-phase modulation, the gain narrowing and gainsaturation) for pulse waveform and compression, get the corresponding waveformchanges. For length factor, get the variation of the amplification indicator. Due to theamplification mechanism difference, for SBS, the paper study the pump parameters,medium parameters, the relative delay, cell length factor in pulse amplification, get thepattern of amplification and the basis for choice of parameters in hundred-picosecond.Finally, based on the enlarge laws in hundred-picosecond, simulated and optimizedthe length and seed optical peak power factors in high power amplification, get theselection basis for the peak power which is amplified more than ten times and pulsewidth of basic non-broadening. By the comprehensive comparing and analysis,discussed the feasibility and the advantages and disadvantages in the given conditions...