Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Scar-like structures and non-integrability in a perfectly square optical
  billiard   We show that scar-like structures (SLS) in a wide aperture vertical cavity
surface emitting laser (VCSEL) can be formed even in a perfectly square
geometry due to interaction of polarization and spatial degrees of freedom of
light. We show also that dissipation in the system induces an order among the
cavity modes, so that SLS become preferred at lasing threshold. More generally,
modes which are more localized both in coordinate and momentum space have in
average lower losses.

7
The categories of this paper are: hep-th
19
The categories of this paper are: eess
4
The categories of this paper are: cond-mat
13
The categories of this paper are: quant-ph
23
The categories of this paper are: solv-int
2
The categories of this paper are: math
36
The categories of this paper are: cmp-lg
21
The categories of this paper are: adap-org
9
The categories of this paper are: nlin
15
The categories of this paper are: nucl-ex
14
The categories of this paper are: math-ph
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
29
The categories of this paper are: funct-an