Joint Laboratory for Attosecond Science, National Research Council of Canada and University of Ottawa, 100 Sussex Drive, Ottawa, Ontario, Canada K1A 0R6.
Phys Rev Lett. 2010 Jun 11;104(23):233904. doi: 10.1103/PhysRevLett.104.233904.
We demonstrate a new method to investigate the origin of spectral structures in high-harmonic generation. We report detailed measurements of high-harmonic spectra in aligned nitrogen and carbon dioxide molecules. Varying the wavelength and intensity of the generating laser field, we show that the minimum in aligned N2 molecules is nearly unaffected, whereas the minimum in aligned CO2 molecules shifts over more than 15 eV. Our quantitative analysis shows that both the interference of multiple orbitals and their structural characteristics affect the position of the minimum. Our method provides a simple approach to the investigation of the high-harmonic generation process in more complex molecules.
我们展示了一种新的方法来研究高次谐波产生中光谱结构的起源。我们报告了在取向氮和二氧化碳分子中高次谐波光谱的详细测量结果。通过改变产生激光场的波长和强度，我们表明在取向 N2 分子中的最小值几乎不受影响，而在取向 CO2 分子中的最小值则移动了超过 15 eV。我们的定量分析表明，多个轨道的干涉及其结构特征都会影响最小值的位置。我们的方法为更复杂分子中的高次谐波产生过程的研究提供了一种简单的方法。
