Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Polarization rotator Bragg grating assisted wavelength selective
  polarization alignment   A device performing both the polarization-alignment and the wavelength
selection is demonstrated by fabricated device. Waveguides incorporating Bragg
gratings for polarization rotation and mode conversion having different widths
are placed near to each other. For the polarization rotation, experimental
results show that the field strength ratio in the two waveguides defines the
diffraction coupling coefficient and excitation strength of unwanted modes. The
excitation of unwanted mode is reduced, when a large radius short curved
waveguide is used for input/output waveguides as shown in the experiment.
Polarization aligned wavelength peaks were observed at the backward drop port
in the experiment.

29
The categories of this paper are: funct-an
34
The categories of this paper are: chem-ph
0
The categories of this paper are: hep-ph
27
The categories of this paper are: comp-gas
9
The categories of this paper are: nlin
14
The categories of this paper are: math-ph
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
28
The categories of this paper are: alg-geom
20
The categories of this paper are: acc-phys
31
The categories of this paper are: ao-sci
10
The categories of this paper are: q-bio
37
The categories of this paper are: supr-con
8
The categories of this paper are: hep-ex
2
The categories of this paper are: math
26
The categories of this paper are: bayes-an