Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonstructural acousto-injection luminescence in metalized lithium
  niobate wafers   We report the observations of nonstructural acousto-injection luminescence
(NAIL) from tantalized LiNbO3 wafers. The samples under study are the X cut or
Y cut wafers with the silver paste electrodes on opposite surfaces. The
thickness is 1 to 2 mm and other linear dimensions are in the range of 2 to 25
mm. Experiments are done at room temperature in the MHz-frequency range. Mainly
the fundamental shear ultrasound modes are excited in the samples.
Experimentally are measured the spectra of NAIL, photo-luminescence spectra,
acousto-electric properties, X Ray diffraction under NAIL. The NAIL and other
effects appear above certain threshold amplitude of the acoustical strain that
is about 10E-5. The involvement of the microstructural non-uniformity in the
effects observed is experimentally identified by the photo-luminescence of
point defects taken from different micro-regions of the samples. The data are
explained in terms of the considerable acoustic stresses and piezoelectric
fields that are capable injecting charge carriers from the metal contacts into
a crystal.

25
The categories of this paper are: patt-sol
8
The categories of this paper are: hep-ex
36
The categories of this paper are: cmp-lg
26
The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
15
The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
34
The categories of this paper are: chem-ph
1
The categories of this paper are: cs
10
The categories of this paper are: q-bio
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
7
The categories of this paper are: hep-th