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A three-step model of high harmonic generation using complex classical trajectories

Koch, Werner
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Abstract

Highlights: • Rigorous trajectory formulation of strong field physics and high harmonic generation. • The Coulomb ground state is represented by an ensemble of complex trajectories. • Trajectories transition seamlessly from the ground state to ionization or recollision. • The ionized wavepacket is reproduced well from the complex trajectories. • Classically allowed and forbidden processes are treated in a single framework. 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.

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71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS73 NUCLEAR PHYSICS AND RADIATION PHYSICSCOULOMB FIELDGROUND STATESHARMONIC GENERATIONHARMONICSIONIZATIONNUCLEIORBITSTUNNEL EFFECTWAVE PACKETS

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Koch, Werner. 2021-04-15. A three-step model of high harmonic generation using complex classical trajectories. https://doi.org/10.1016/j.aop.2020.168288

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