State Key Laboratory of Molecular Reaction Dynamics, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
J Chem Phys. 2012 Feb 7;136(5):054102. doi: 10.1063/1.3681165.
In this paper, we theoretically investigate the nuclear signatures effects, i.e., the initial vibrational state and the isotopic effects on the generations of the molecular high-order harmonics and the attosecond pulses when the model H(2)(+)/D(2)(+) ions are exposed to a 5 fs/800 nm chirp pulse. The numerical solution of the time-dependent Schrödinger equation for these vibrating molecule ions shows that the intensities of the harmonic spectra are reinforced with the enhancement of the initial vibrational state. Moreover, through the investigation of the isotopic effect, we find that more intense harmonics are generated in the lighter nucleus. Furthermore, by optimizing the chirp pulse under the optimal initial vibrational state, an intense ultrabroad supercontinuum with a 325 eV bandwidth can be obtained. By properly superposing the harmonic spectrum, an attosecond pulse as short as 57 as (16 as) is generated without (with) phase compensation.
本文从理论上研究了核签名效应对模型 H(2)(+)/D(2)(+) 离子在 5 fs/800nm 啁啾脉冲作用下产生分子高次谐波和阿秒脉冲的影响，即初始振动状态和同位素效应。这些振动分子离子的含时薛定谔方程的数值解表明，随着初始振动状态的增强，谐波谱的强度得到增强。此外，通过对同位素效应的研究，我们发现较轻核中产生的谐波强度更大。此外，通过在最佳初始振动状态下优化啁啾脉冲，可以获得带宽为 325eV 的强超连续谱。通过适当叠加谐波谱，可以在没有（有）相位补偿的情况下产生短至 57as（16as）的阿秒脉冲。
