CONTROL THE GAIN-NARROWING IN FEMTOSECOND Ti:SAPPHIRE AMPLIFIER BY SHAPING OSCILLATOR PULSE

Numeric simulation of compensating gain-narrowing in femtosecond Ti:sapphire amplifier by shaping seed pulse is made in this paper, the gain spectral narrowing process are compared for multipass amplifiers with general and shaping seeding pulses injection respectively. On this base,we define the band width narrowing ratio,the simulation results show the gain-narrowing effect can be well overcome by shaping laser pulses from oscillator.