饱和吸收效应提高800nm超短脉冲激光信噪比
Increase of SNR of ultra-short pulse laser at 800nm with saturated absorption
中国工程物理研究院 激光聚变研究中心,绵阳 621900
摘要
为了提高超短脉冲激光的信噪比,研究了钕玻璃在800nm波段附近的饱和吸收特性,通过速率方程计算得到了组合钕玻璃系统的非线性透射率与归一化能量密度的关系曲线。对任意一800nm激光脉冲,利用放大自发辐射脉冲、调制脉冲等噪声与激光主脉冲在频谱特性方面的差异,采取了对不同类型的钕玻璃材料进行组合的方法,对材料的掺杂浓度、厚度等综合数据进行优化,合理设计了组合钕玻璃系统的吸收谱。计算模拟结果表明,该研究有效抑制了噪声,能实现较高幅度的高信噪比。
Abstract
High signal-to-noise ratio(SNR) is very important in the interaction between high energy ultra-short laser and materials.In order to increase the SNR of ultra-short laser,the saturation absorption property of Nd:glass laser at the neighborhood of 800nm was studied.The relationship between the nonlinear transmissivity and normalized energy density of the combined Nd:glass system was obtained after solving the rate equations.For an optional 800nm laser pulse,making use of the frequency differences between amplified spontaneous emission pulse,modulation pulse and the main laser pulse,combining different types of Nd:glass material of optimizing the comprehensive data of the density,thickness...etc,the absorption spectrum of the combined Nd:glass system was designed reasonably.Computation results indicate that the noise is compressed effectively,and the SNR is increased a lot.
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陈林, 贺少勃, 隋展, 刘建国, 刘勇, 陈远斌, 景峰. 饱和吸收效应提高800nm超短脉冲激光信噪比[J]. 激光技术, 2009, 33(4): 340. CHEN Lin, HE Shao-bo, SUI Zhan, LIU Jian-guo, LIU Yong, CHEN Yuan-bin, JING Feng. Increase of SNR of ultra-short pulse laser at 800nm with saturated absorption[J]. Laser Technology, 2009, 33(4): 340.
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