飞秒激光参数对三态梯度型分子态布居数的影响

Effects of femtosecond laser parameters on state populations of three-level ladder molecule

利用含时波包法研究并且首次量化了强飞秒泵浦-探测激光场中泵浦场强、泵浦波长和脉宽对三态梯度型K2分子态布居数的影响。泵浦场强、泵浦波长和脉宽影响Rabi振荡,而Rabi振荡的变化又导致了基态和激发态布居数周期性变化。量化这3个激光场参数对激发态布居数的影响验证了此周期性变化规律,表明变化频率随着泵浦场强和脉宽的增大而变化。研究表明调节激光场参数可实现对态布居数的选择性分布,可以为实验上实现分子的光控制提供重要参考。

The effects of the pump intensity, the wavelength and the pulse width on the state populations of the three-level ladder K2 molecule driven by intense femtosecond pump-probe pulses are investigated by employing the time-dependent wave packet approach andare thus quantified. The Rabi oscillation is affected by the pump intensity, the wavelength and the pulse width, and its variation results in aperiodical change of the populations in the ground state and the excited state. Quantifying their effects on the population of the excited stateverifies the periodical nature and shows that the frequency varies with the increasing pump intensity and pulse width. The results illustratethat the needed population in the electronic state of interest can be obtained by controlling these parameters, which provides someimportant basis for light manipulation of molecular processes.