Small Phase Space Structures and their Relevance to Pulsed Quantum Evolution: the Stepwise Ionization of the Excited Hydrogen Atom in a Microwave Pulse

TL;DR

This paper investigates how classical phase-space structures influence quantum stepwise ionization in a hydrogen atom under microwave pulses, revealing a deep connection between classical dynamics and quantum behavior.

Contribution

It demonstrates that quantum ionization steps are directly related to classical phase-space metamorphoses, bridging classical and quantum descriptions of atomic ionization.

Findings

Quantum and classical models show matching stepwise ionization patterns.

Ionization steps are linked to specific phase-space metamorphoses.

Two-level interactions in quantum dynamics correspond to classical phase-space structures.

Abstract

Experiments have shown that the microwave ionization probability of a highly excited almost monodimensional hydrogen atom subjected to a microwave pulse sometimes grows in steps when the peak electric field of the pulse is increased. Classical pulsed simulations display the same steps, which have been traced to phase-space metamorphoses. Quantum numerical calculations again exhibit the same ionization steps. I show that the time-sequence of two level interactions, responsible for the observed steps in the quantum picture, is strictly related to the classical phase space structures generated by the above mentioned metamorphoses.