We present a new trajectory formulation of high harmonic generation that treats classically allowed and classically forbidden processes within a single dynamical framework. Complex trajectories orbit the nucleus, producing the stationary Coulomb ground state. When the field is turned on, these complex trajectories continue their motion in the field-dressed Coulomb potential and therefore tunnel ionization, unbound evolution and recollision are described within a single, seamless framework. The new formulation can bring mechanistic understanding to a broad range of strong field physics effects.

中文翻译：

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使用复杂经典轨迹的高次谐波生成三步模型

我们提出了一种新的高谐波生成轨迹公式，它在单个动力学框架内处理经典允许和经典禁止的过程。复杂的轨迹围绕原子核运行，产生静止的库仑基态。当场被打开时，这些复杂的轨迹在场修饰的库仑势中继续它们的运动，因此在一个单一的、无缝的框架内描述了隧道电离、无约束演化和再碰撞。新公式可以为广泛的强场物理效应带来机械理解。