Department of Electrical Engineering, Technion-Israel Institute of Technology, Haifa 32000, Israel.
Opt Lett. 2012 Aug 1;37(15):3024-6. doi: 10.1364/OL.37.003024.
We show, by using numerical simulations, that self-similar pulses with a duration on the order of few nanoseconds and an energy on the order of 10 μJ can be obtained at the output of a fiber Bragg grating (FBG) written in a fiber amplifier. The evolution of the amplified pulses is determined by the combined effect of Kerr nonlinearity, normal-dispersion, gain, and gain saturation, which limit the pulse energy. The output pulse mainly depends on the initial pulse energy rather than on the initial pulse profile. The reduced group velocity in FBGs can significantly increase the total gain for a given amplifier length. Hence we find that the proposed amplification scheme can be highly advantageous for amplification of nanosecond-scale pulses in fiber amplifiers.
我们通过数值模拟表明，在光纤放大器中写入光纤布拉格光栅（FBG）后，可在输出端获得持续时间为数纳秒量级、能量为数微焦耳量级的自相似脉冲。受克尔非线性、正常色散、增益和增益饱和的综合影响，放大脉冲的演化限制了脉冲能量。输出脉冲主要取决于初始脉冲能量，而与初始脉冲形状关系不大。在 FBG 中，群速度的降低可以显著增加给定放大器长度的总增益。因此，我们发现，所提出的放大方案非常有利于光纤放大器中纳秒级脉冲的放大。
