A new time-frequency method to reveal quantum dynamics of atomic hydrogen in intense laser pulses: Synchrosqueezing Transform

TL;DR

This paper presents a novel synchrosqueezing transform (SST) method for analyzing quantum dynamics of hydrogen atoms in intense laser fields, revealing detailed processes like selection rules and high harmonic generation.

Contribution

The study introduces an adaptive time-frequency analysis technique, SST, providing a new approach for exploring quantum dynamics at an ab initio level.

Findings

SST effectively depicts quantum processes such as selection rules and AC Stark effects.

The method reveals high harmonic generation in hydrogen atoms.

SST offers a versatile tool for quantum dynamics analysis.

Abstract

This study introduces a new adaptive time-frequency (TF) analysis technique, synchrosqueezing transform (SST), to explore the dynamics of a laser-driven hydrogen atom at an {\it ab initio} level, upon which we have demonstrated its versatility as a new viable venue for further exploring quantum dynamics. For a signal composed of oscillatory components which can be characterized by instantaneous frequency, the SST enables rendering the decomposed signal based on the phase information inherited in the linear TF representation with mathematical support. Compared with the classical type TF methods, the SST clearly depicts several intrinsic quantum dynamical processes such as selection rules, AC Stark effects, and high harmonic generation.