利用啁啾-紫外组合激光增大谐波能量及强度

量子电子学报 ›› 2019, Vol. 36 ›› Issue (6): 738-744.

利用啁啾-紫外组合激光增大谐波能量及强度

李义，冯立强*

辽宁工业大学理学院，辽宁锦州 121001

收稿日期:2019-03-28 修回日期:2019-05-30 出版日期:2019-11-28 发布日期:2019-11-19
通讯作者: 冯立强 E-mail:lqfeng1101@126.com
作者简介:李义 (1978-)，博士，副教授，主要从事强激光场中电子动力学行为理论方面的研究。
基金资助:
Supported by National Natural Science Foundation of China（国家自然科学基金，11504151)

Improvement of harmonic cutoff and intensity by using chirped-UV combined field

LI Yi, FENG Liqiang*

College of Science, Liaoning University of Technology, Jinzhou 121001, China

Received:2019-03-28 Revised:2019-05-30 Published:2019-11-28 Online:2019-11-19

摘要/Abstract

摘要： 为了延伸谐波截止能量并增强谐波辐射强度，提出了一种利用啁啾激光与紫外激光的组合场驱动He原子调控谐波辐射过程的方法。结果表明：在单色激光驱动下，随着负向啁啾的加入，谐波截止能量得到延伸。并且，随着激光脉宽的增大，谐波截止能量进一步延伸。引入第二束激光场时，谐波截止能量有少许延伸，同时，谐波辐射强度有3个数量级的增强。引入第三束紫外激光场时，谐波辐射强度与双色场比较有2个数量级的增强。随着紫外激光光强增大，谐波辐射强度进一步增强。最后，通过叠加光谱连续区的谐波可获得脉宽在38 as的孤立阿秒脉冲。

关键词: 激光物理, 高次谐波, 孤立阿秒脉冲, 啁啾激光, 紫外激光

Abstract: In order to extend harmonic cutoff energy and enhance harmonic radiation intensity, a method using the combined field of chirped laser and ultraviolet laser to drive He atoms to regulate the harmonic radiation process is proposed. Results show that driven by the single-color field, the harmonic cutoff energy is extended with the introduction of negative chirp. Moreover, as the laser pulse width increases, the harmonic cut-off energy further extends. When the second laser field is introduced, the harmonic cutoff energy extends slightly. At the same time, the harmonic radiation intensity is enhanced by three orders of magnitude. When the third beam ultraviolet laser field is introduced, the harmonic radiation intensity is enhanced by two orders of magnitude compared with that of the two-color field. As the intensity of ultraviolet laser is increased, the intensity of harmonic radiation is further enhanced. Finally, an isolated attosecond pulse with a pulse width of 38 as can be obtained by superposing the harmonics of the spectral continuum region.

Key words: laser physics, high-order harmonic generation, isolated attosecond pulse, chirped pulse, ultraviolet pulse

中图分类号:

O562.4

李义, 冯立强. 利用啁啾-紫外组合激光增大谐波能量及强度[J]. 量子电子学报, 2019, 36(6): 738-744.

LI Yi, FENG Liqiang. Improvement of harmonic cutoff and intensity by using chirped-UV combined field[J]. Chinese Journal of Quantum Electronics, 2019, 36(6): 738-744.

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