Self-similar regenerative amplification method and apparatus for femtosecond laser chirped pulses

A self-similar regenerative amplification method for femtosecond laser chirped pulses, comprising:

• continuously injecting seed pulses into a spectrum shaping broader, performing a time domain broadening process on the injected seed pulses by a time domain broader, and performing spectrum shaping on the broadened pulses by a spectrum shaper during or after the time domain broadening process, to obtain saddle chirped pulses:
• injecting the saddle chirped pulses into a regenerative amplification chamber of a self-similar regenerative amplifier, and obtaining gains in spectrums of the saddle chirped pulses after multiple stepwise amplifications back and forth in the regenerative amplification chamber by a gain crystal and a nonlinear crystal to transfer spectrum intensities of the saddle chirped pulses evolve from a saddle shape to a flat shape:
• performing multiple stepwise amplifications back and forth on flat chirped pulses in the regenerative amplification chamber using the gain crystal, so that when a pulse peak power exceeds a MW level, nonlinear spectrum broadening is accomplished on the flat chirped pulses by the nonlinear crystal;
• in the process of regenerative amplification, after the chirped pulses pass through a gain medium as a focused light spot and then pass through a nonlinear medium as the focused light spot after being collimated by a lens, enhancing the nonlinear spectrum broadening to enable the chirped pulses after self-similar amplification to reach gain saturation, and outputting high-energy chirped pulses;
• and
• injecting the high-energy chirped pulses after gain saturation into a pulse compressor, and outputting compressed pulses after pulse compression of the high-energy chirped pulses by the pulse compressor.