静电场与非共振脉冲激光电场共同作用下分子取向的机制

本分析了静电场与非共振的线偏振激光脉冲电场共同作用下分子取向的机制，发现如果激光脉冲足够宽，当激光光强确定后，脉冲的形状对分子取向起着决定性的作用。中进一步挖掘了这种现象背后分子取向的机制，得出了获得高效分子取向的必要条件，并建议将所得的结论应用于短脉冲下的‘postpulse orientation’。     

Simultaneous Extension and Enhancement of the HHG Plateau by Using Combined Lasers Irradiating on a United Two-Atom System

We present the high-order harmonic generation spectrum from a united two-atom system simultaneously exposed to a fundamental Ti:sapphire and its 33rd harmonic (H33) lasers by numerically solving a one-dimensional timedependent Schroedinger equation. At a suitable inter-nuclear separation, the harmonic plateau is widened from Ip 3.2Up in the single-atom case up to Ip 5.6Up in the united-atom case. Furthermore, the plateau is heightened in excess of six orders of magnitude by using the combined lasers compared with the case of the fundamental laser alone. Such a scheme can step by step accomplish the following processes: through a single H33 photon resonance transition an appropriate amount of electrons are first populated to an excited state, in which the electrons are easily ionized and subsequently accelerated by the fundamental laser; then they can recombine with the neighbouring atom, so that high-efficiency emissions of the harmonics beyond Ip 3.2Up are successfully realized.     

广义Floquet理论下分子的持续过场取向

本文运用广义Floquet方法找到了一组分子转动态的特殊相干叠加态,从该态出发,分子的过场取向可被延续任意长的时间;运用双重复周期的外场,我们在外场脉冲时间间隔较大的不利情况下提高了分子取向程度,并且分析了Floquet方法下分子取向的优点及获得高程度取向的机制.     

Field-Free Orientation of Molecules with Small Permanent Dipole Moments by Using a Train of Half-Cycle Pulses

We present a scheme aiming at the field-free orientation of molecules with smaller permanent dipole moments under the framework of the half-cycle pulse (HCP) method. Taking the HCCCI molecule as an example, we show that a train of identical HCPs with special time intervals can considerably raise the level of the orientation. The scheme is analytically interpreted in terms of intermittent Rabi oscillations by referring to a simplified two-state model.     

静电场与非共振脉冲激光电场共同作用下分子取向的机制

本文分析了静电场与非共振的线偏振激光脉冲电场共同作用下分子取向的机制,发现如果激光脉冲足够宽,当激光光强确定后,脉冲的形状对分子取向起着决定性的作用.文中进一步挖掘了这种现象背后分子取向的机制,得出了获得高效分子取向的必要条件,并建议将所得的结论应用于短脉冲下的‘post-pulse orientation'.