A novel project of amplifying equally the high repetition ultra-short signal optical pulse is explored in semiconductor optical amplifiers. It is shown that the signal optical pulse can be amplified equally by injecting another copropagating strong assistant optical pulse into semiconductor optical amplifiers. It is asked that the assistant optical pulse lags behind the signal pulse, and has right initial peak power for assistant optical pulse, and the wavelength of signal pulse is locates in the gain bandwidth, and the wavelength of assistant pulse is far from the gain bandwidth.
After presenting an improved theoretical model that describes the dynamic process of optical pulse amplification by the semiconductor light amplifiers (SLAs), both the rising and falling time of amplified picosecond optical pulses by the SLAs have been investigated numerically. The results show that with the increase of the bias current of SLAs, the rising time will decrease and the falling time increase; the input pulse with a large peak power will accelerate the rising time shortening and the falling time lengthening; the gain compression has an obvious influence on the rising and falling time for several picosecond width input pulses; the gain asymmetry and shift violently affects the rising and falling time.