Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A new time-frequency method to reveal quantum dynamics of atomic
  hydrogen in intense laser pulses: Synchrosqueezing Transform   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.

13
The categories of this paper are: quant-ph
27
The categories of this paper are: comp-gas
37
The categories of this paper are: supr-con
26
The categories of this paper are: bayes-an
28
The categories of this paper are: alg-geom
4
The categories of this paper are: cond-mat
5
The categories of this paper are: gr-qc
30
The categories of this paper are: q-alg
22
The categories of this paper are: chao-dyn
16
The categories of this paper are: stat
35
The categories of this paper are: mtrl-th
6
The categories of this paper are: astro-ph
20
The categories of this paper are: acc-phys
24
The categories of this paper are: dg-ga
0
The categories of this paper are: hep-ph
19
The categories of this paper are: eess