利用频率相近的双色激光驱动氢原子产生单个短脉冲

J4 ›› 2013, Vol. 30 ›› Issue (4): 405-410.

利用频率相近的双色激光驱动氢原子产生单个短脉冲

杨奕婷,乔豪学

武汉大学物理科学与技术学院, 湖北武汉 430072

收稿日期:2012-08-28 修回日期:2012-09-29 出版日期:2013-07-28 发布日期:2013-07-06
通讯作者: 乔豪学（1970-）湖北恩施人，教授，博士生导师，主要从事原子分子物理理论研究。 E-mail:qhx@whu.edu.cn
作者简介:杨奕婷（1986-）研究生，主要从事强激光场下原子高次谐波的理论研究。E-mail:ceciyang211@163.com

Single short pulse generated by hydrogen atom exposed to the combined field of two laser pulses with similar frequency

YANG Yiting, QIAO Haoxue

School of Physics Science and Technology, Wuhan University, Wuhan 430072, China

Received:2012-08-28 Revised:2012-09-29 Published:2013-07-28 Online:2013-07-06

摘要/Abstract

摘要： 通过研究双色场中三维氢原子的高次谐波，发现当作为驱动源的两束光频率比为3:5，且附加光相对于基本光的强度比落在某个特殊值时(0.35)，叠加截止区的高次谐波能直接得到单个的短脉冲。提出利用双色场获取单个短脉冲的新方案，该方案的要点是：作为驱动源的两束光，频率需要是比较接近的奇数比；附加光的相对强度需要是一个特殊值，使不同通道间的干涉相消抑制其它脉冲。在进一步的研究中可选取束缚能更高的原子，扩展截止区的位置，使得到单脉冲的脉宽更窄。

关键词: 激光物理, 单个短脉冲, 双色激光场, 三维氢原子的高次谐波, 量子通道

Abstract: The high order harmonic generations of three-dimensional hydrogen atom which exposed to the combination of two laser pulses have been studied. When the combined field has a proper frequency ratio(3:5), and the relative intensity of the additional laser field reaches a specific value(0.35), the single short pulse can be obtained directly. A new method to obtain the single short pulse is proposed, the main points of the method are: the frequency ratio of the two lasers should be adjacent odd, and the relative intensity of the additional laser to the basic laser should fall on a particular value. In future research, the atoms with a higher binding energy can be chosen, the width of HHG’s plateau will be enlarged, so the width of pulse will be reduced.

Key words: laser physics, single short pulse; bichromatic laser field, high order harmonic generations of three-dimensional hydrogen atom, quantum pathway

中图分类号:

TN241

杨奕婷乔豪学. 利用频率相近的双色激光驱动氢原子产生单个短脉冲[J]. J4, 2013, 30(4): 405-410.

YANG Yiting, QIAO Haoxue. Single short pulse generated by hydrogen atom exposed to the combined field of two laser pulses with similar frequency[J]. J4, 2013, 30(4): 405-410.

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