High-order-harmonic generation from diatomic molecules in driving fields with nonvanishing ellipticity: A generalized interference condition
High-order-harmonic generation from diatomic molecules in driving fields with nonvanishing ellipticity: A generalized interference condition
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DOI：
10.1103/physreva.88.023404
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发表时间：
2013-08-05
影响因子：
2.9
通讯作者：
Faria, C. Figueira de Morisson
中科院分区：
文献类型：
--
作者：
Das, T.;Augstein, B. B.;Faria, C. Figueira de Morisson
我们研究了强驱动场对定向双原子分子高次谐波谱的影响，强驱动场的偏振分量呈现正交性。在强场近似和单激活电子近似下，我们导出了一个广义的双中心干涉条件，它考虑了s-p混合和轨道对称性。我们表明，非零椭圆度引入了一个有效的动态位移的角度，两个中心的干涉最大值和最小值发生，关于现有的条件为线性偏振场。这种位移取决于返回电子沿沿着每个可能轨道平行和垂直于椭圆主轴的场修饰动量分量之间的比率。由于这种依赖性，我们发现，将有一个模糊的两个中心的干涉极小值，并增加椭圆率导致分裂在这样的模式。这些功能进行了详细的调查，为H-2和Ar-2在一个双色场组成的两个正交偏振波。
We investigate the influence of intense driving fields whose components exhibit orthogonal polarizations on high-order-harmonic spectra from aligned diatomic molecules. We derive a generalized two-center interference condition, which accounts for s-p mixing and the orbital symmetry, within the strong-field and the single-active electron approximation. We show that the nonvanishing ellipticity introduces an effective dynamic shift in the angle for which the two-center interference maxima and minima occur, with regard to the existing condition for linearly polarized fields. This shift depends on the ratio between the field-dressed momentum components of the returning electron parallel and perpendicular to the major ellipticity axis along each possible orbit. Because of this dependence, we find that there will be a blurring in the two-center interference minima, and that increasing ellipticity leads to splitting in such patterns. These features are investigated in detail for H-2 and Ar-2 in a bichromatic field composed of two orthogonally polarized waves.