Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Non-exhibition of Bragg phenomenon by chevronic sculptured thin films:
  experiment and theory   The unit cell of a chevronic sculptured thin film (ChevSTF) comprises two
identical columnar thin films (CTFs) except that the nanocolumns of the first
are oriented at an angle \chi and nanocolumns of the second are oriented at an
angle \pi-\chi with respect to the interface of the two CTFs. A ChevSTF
containing 10 unit cells was fabricated using resistive-heating physical vapor
deposition of zinc selenide. Planewave reflectance and transmittance spectrums
of this ChevSTF were measured for a wide variety of incidence conditions over
the 500--900-nm range of the free-space wavelength. Despite its structural
periodicity, the ChevSTF did not exhibit the Bragg phenomenon. Theoretical
calculations with the CTFs modeled as biaxial dielectric materials indicated
that the Bragg phenomenon would not be manifested for normal and near-normal
incidence, but vestigial manifestation was possible for suffciently oblique
incidence. Thus, structural periodicity does not always lead to electromagnetic
periodicity that underlies the exhibition of the Bragg phenomenon.

22
The categories of this paper are: chao-dyn
15
The categories of this paper are: nucl-ex
19
The categories of this paper are: eess
0
The categories of this paper are: hep-ph
6
The categories of this paper are: astro-ph
13
The categories of this paper are: quant-ph
26
The categories of this paper are: bayes-an
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
12
The categories of this paper are: nucl-th
24
The categories of this paper are: dg-ga
7
The categories of this paper are: hep-th
14
The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
20
The categories of this paper are: acc-phys
21
The categories of this paper are: adap-org