高功率超短脉冲激光系统中光谱增益窄化补偿的调制函数

Spectral gain narrowing compensation modulation function in high-power ultrashort-pulse laser system

设计了一种与高功率超短脉冲激光放大过程中获得的总增益、增益介质的带宽、激光带宽、脉冲中心波长等参数相关的调制函数,对激光放大过程中的光谱增益窄化进行补偿。此调制函数的优越性在于,对不同性能的激光系统,无需改变调制函数的形式就能适用。通过数值模拟的方法,讨论了在不同增益介质带宽、激光带宽、脉冲中心波长下的补偿效果。此调制函数在高功率超短脉冲激光系统中有良好的应用前景。

A modulation function related to the total gain of amplifier chains was established to compensate the spectral gain narrowing in high-power ultrashort-pulse laser systems. The modulation function to be used for a system could be given by putting in all data of the system, including the spectrum of the total gain, bandwidths of the gain medium and laser pulse, and central wavelength. For different laser systems, the form of the modulation function could remain the same. Spectral compensation simulations for the SILEX-I Ti:sapphire laser system were conducted by modulating the seeding pulse with a designed function at different parameters of bandwidth of gain medium, laser spectral width and laser central wavelength etc. The simulation results indicate that this modulated function is very good for gain narrowing compensation. If the bandwidths of the gain medium can reach 220 nm, by modulating the seeding pulse, the output spectrum width will increase 15 nm or more.