空间非均匀场下H2+分子发射谐波及阿秒脉冲的理论研究

摘要/Abstract

摘要： 理论研究了空间非均匀场下H2+分子发射高次谐波及阿秒脉冲的特点。计算结果表明，适当调节H2+分子的核间距离及空间非均匀参数，不仅谐波发射的截止能量得到延伸，而且谐波谱的干涉结构也明显减小。随后引入单极控制激光场，谐波截止能量得到进一步扩展，形成一个由单一量子路径贡献而成的530eV的超长平台区。最后，通过叠加谐波，可获得脉宽范围在32as到46as的X射线光源。

关键词: 激光物理, 高次谐波, 阿秒脉冲, H2+分子, 空间非均匀激光场, laser physics, high-order harmonic generation, attosecond pulse, H2+ molecule, spatial inhomogeneous field

Abstract: High-order harmonic emission and attosecond pulse generation from H2+ molecule ion driven by the spatial inhomogeneous laser field have been theoretically investigated. The results show that by properly choosing the internuclear distance and the spatial inhomogeneous parameter of the fundamental pulse, not only the harmonic cutoff is remarkably enhanced, but also the harmonic modulation is reduced. Further, with the introduction of the controlling unipolar pulse, the harmonic cutoff has been further extended, resulting in a 530eV bandwidth with the single quantum path contribution. Finally, by properly superposing the selected harmonics, a series of attosecond X-ray pulses with the durations from 32as to 46as can be obtained.

中图分类号:

O562.4

刘航冯立强. 空间非均匀场下H2+分子发射谐波及阿秒脉冲的理论研究[J]. J4, 2017, 34(2): 162-168.

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