Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Few-cycle excitation of atomic coherence: A closed-form analytical
  solution beyond the rotating-wave approximation   Developing an analytical theory for atomic coherence driven by ultrashort
laster pulses has proved to be challenging due to the breakdown of the rotating
wave approximation (RWA). In this paper, we present an approximate, closed-form
solution to the Schrodinger equation that describes a two-level atom under the
excitation of a far-off-resonance, few-cycle pulse of arbitrary shape without
invoking the RWA. As an example of its applicability, an analytical solution
for Gaussian pulses is explicitly given. Comparisons with numerical solutions
validate the accuracy our solution within the scope of the approximation.
Finally, we outline an alternative approach that can lead to a more accurate
solution by capturing the nonlinear behaviors of the system.

32
The categories of this paper are: atom-ph
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
16
The categories of this paper are: stat
4
The categories of this paper are: cond-mat
24
The categories of this paper are: dg-ga
21
The categories of this paper are: adap-org
6
The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
11
The categories of this paper are: hep-lat
31
The categories of this paper are: ao-sci
22
The categories of this paper are: chao-dyn
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
9
The categories of this paper are: nlin
18
The categories of this paper are: econ