Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Symmetry-protected non-Abelian geometric phases in optical waveguides
  with nonorthogonal modes   The generation of non-Abelian geometric phases from a system of evanescently
coupled waveguides is extended towards the framework of nonorthogonal
coupled-mode theory. Here, we study an experimentally feasible tripod
arrangement of waveguides that contain dark states from which a nontrivial
U(2)-mixing can be obtained by means of an adiabatic parameter variation. We
investigate the influence of higher-order contributions beyond
nearest-neighbour coupling as well as self-coupling on the stability of a
U(3)-phase generated from an optical tetrapod setup. Our results indicate that,
despite the mode nonorthogonality, the symmetry of dark states protects the
geometric evolution of light from distortion.

6
The categories of this paper are: astro-ph
4
The categories of this paper are: cond-mat
33
The categories of this paper are: plasm-ph
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
34
The categories of this paper are: chem-ph
26
The categories of this paper are: bayes-an
15
The categories of this paper are: nucl-ex
31
The categories of this paper are: ao-sci
32
The categories of this paper are: atom-ph
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int