Open-loop and closed-loop control of dissociative ionization of ethanol in intense laser fields
Open-loop and closed-loop control of dissociative ionization of ethanol in intense laser fields
复制标题
DOI：
10.1063/1.2200706
复制
发表时间：
2006-05-28
影响因子：
4.4
通讯作者：
Yamanouchi, Kaoru
中科院分区：
文献类型：
--
作者：
Yazawa, Hiroki;Tanabe, Takasumi;Yamanouchi, Kaoru
在强激光场（10¹³ - 10¹⁵ 瓦/平方厘米）中，通过开环和闭环优化程序，乙醇阳离子C₂H₅OH⁺ 中C - O键断裂相对于C - C键断裂的相对产率得以最大化。在开环优化中，合成了一系列强激光脉冲，使得第一个和最后一个脉冲之间的时间间隔为800飞秒，并且系统地改变一个脉冲序列内脉冲的数量和宽度。当通过增加脉冲数量或拉伸三脉冲序列中的所有脉冲，使800飞秒的时长充满激光场时，C - O键断裂的相对产率会显著增大。在使用自学习算法的闭环优化中，采用强激光脉冲的四个色散系数或128个频率分量的相位作为优化参数。从这些优化实验中发现，只要强激光场的总持续时间达到约1皮秒，C - O键断裂的产率比就会最大化，并且脉冲内激光场的间歇性消失不会影响键断裂途径的相对产率。（c）2006美国物理学会。
The relative yield of the C-O bond breaking with respect to the C-C bond breaking in ethanol cation C2H5OH+ is maximized in intense laser fields (10(13)-10(15) W/cm(2)) by open-loop and closed-loop optimization procedures. In the open-loop optimization, a train of intense laser pulses are synthesized so that the temporal separation between the first and last pulses becomes 800 fs, and the number and width of the pulses within a train are systematically varied. When the duration of 800 fs is filled with laser fields by increasing the number of pulses or by stretching all pulses in a triple pulse train, the relative yield of the C-O bond breaking becomes significantly large. In the closed-loop optimization using a self-learning algorithm, the four dispersion coefficients or the phases of 128 frequency components of an intense laser pulse are adopted as optimized parameters. From these optimization experiments it is revealed that the yield ratio of the C-O bond breaking is maximized as far as the total duration of the intense laser field reaches as long as similar to 1 ps and that the intermittent disappearance of the laser field within a pulse does not affect the relative yields of the bond breaking pathways. (c) 2006 American Institute of Physics.