强laser场中经典允许动力学的实时量子轨道
Real-time quantum trajectories for classically allowed dynamics in strong laser fields
摘要：
在强红外场中原子和分子动力学的物理图象及其理论描述都使用电子轨道的概念。在这里，我们解决一个关键的问题，在这种情况下出现的：这些轨迹的明显的量子特征，如复值坐标，物理上相关的经典允许的相空间区域，是什么是他们的起源？首先，我们认为经典运动方程的解可以解释量子效应。为此，我们构造了一个精确的解决方案，经典的Hamilton-Jacobi方程占动力学的波包，并表明，这种解决方案是物理正确的限制$\hbar \to 0$。其次，我们表明，经典轨迹的虚部直接链接到有限大小的初始波包在动量空间。这样，如果在强红外场中由光隧穿产生的电子波包在坐标和动量上都是局部化的，则其隧穿后的运动{ \em ipso facto\/}不能用纯粹的经典轨迹来描述-与文献中流行的模型相反。
英文摘要：
Both the physical picture of the dynamics of atoms and molecules in intense infrared fields and its theoretical description use the concept of electron trajectories. Here we address a key question which arises in this context: Are distinctly quantum features of these trajectories, such as the complex-valued coordinates, physically relevant in the classically allowed region of phase space, and what is their origin? First, we argue that solutions of classical equations of motion can account for quantum effects. To this end, we construct an exact solution to the classical Hamilton-Jacobi equation which accounts for dynamics of the wave packet, and show that this solution is physically correct in the limit $\hbar \to 0$. Second, we show that imaginary components of classical trajectories are directly linked to the finite size of the initial wavepacket in momentum space. This way, if the electronic wavepacket produced by optical tunneling in strong infrared fiels is localised both in coordinate and momentum, its motion after tunneling {\em ipso facto\/} cannot be described with purely classical trajectories -- in contrast to popular models in the literature.
机构、总结、中文摘要均由AI分析而来，可能存在错误，请以论文正文为准。
