High-Order harmonic generation of aligned acetylene in elliptically polarized strong laser fields
High-Order harmonic generation of aligned acetylene in elliptically polarized strong laser fields
复制标题
DOI：
10.1063/1674-0068/31/cjcp1805117
复制
发表时间：
2018-08
影响因子：
1
通讯作者：
Hongjing Liang;Qiao-xia Wang;Xin Fan;L. Shan;Shuang Feng;B. Yan;R. Ma;Haifeng Xu
中科院分区：
文献类型：
--
作者：
Hongjing Liang;Qiao-xia Wang;Xin Fan;L. Shan;Shuang Feng;B. Yan;R. Ma;Haifeng Xu
利用自制的高次谐波谱仪，实验研究了在35-fs 800 nm强激光场作用下，乙炔分子排列产生的高次谐波。观察到分子的HHG概率随着激光椭圆度的增加而下降，这与众所周知的隧穿+再散射情景的推论一致。通过引入弱飞秒激光脉冲对分子进行非绝热排列，研究了线性偏振和椭圆偏振驱动激光场下分子轨道对HHG的影响。结果表明，当分子轴与激光电场垂直排列时，谐波强度最大。结果表明，最高已占据分子轨道（HOMO）和HOMO-1都是导致乙炔分子强场HHG的原因。我们的研究为理解分子与超快强激光场的相互作用铺平了道路。
We perform an experimental study on high-order harmonic generation (HHG) of aligned acetylene molecules induced by a 35-fs 800-nm strong laser field, by using a home-built HHG spectrometer. It is observed that the molecular HHG probability declines with increasing the laser ellipticity, which is in consistence with the deduction from the well-known tunneling-plus-rescattering scenario. By introducing a weak femtosecond laser pulse to non-adiabatically align the molecules, we investigated the molecular orbital effect on the HHG in both linearly and elliptically polarized driving laser fields. The results show that the harmonic intensity is maximum for the molecular axis aligned perpendicularly to the laser electric field. It indicates that both the highest occupied molecular orbitals (HOMO) and HOMO-1 contribute to the strong-field HHG of acetylene molecules. Our study should pave the way for understanding the interaction of molecules with ultrafast strong laser fields.