Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Surface Acoustic Wave Amplification by DC-Voltage Supplied to Graphene
  Film   Using a high-resolution X-Ray diffraction measurement method, the surface
acoustic waves (SAW) propagation in a graphene film on the surface of a
Ca3TaGa3Si2O14 (CTGS) piezoelectric crystal was investigated, where an external
current was driven across the graphene film. Here we show for the first time
that the application of the DC field leads to a significant enhancement of the
SAW magnitude and, as a result, to amplification of the diffraction satellites.
Amplification of 33.2 dB/cm for the satellite +1, and of 13.8 dB/cm for the
satellite +2, at 471 MHz has been observed where the external DC voltage of
+10V was applied. Amplification of SAW occurs above a DC field much smaller
than that of a system using bulk semiconductor. Theoretical estimates are in
reasonable agreement with our measurements and analysis of experimental data
for other materials.

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The categories of this paper are: atom-ph
11
The categories of this paper are: hep-lat
19
The categories of this paper are: eess
6
The categories of this paper are: astro-ph
7
The categories of this paper are: hep-th
21
The categories of this paper are: adap-org
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
35
The categories of this paper are: mtrl-th
22
The categories of this paper are: chao-dyn
26
The categories of this paper are: bayes-an
33
The categories of this paper are: plasm-ph
23
The categories of this paper are: solv-int
34
The categories of this paper are: chem-ph
18
The categories of this paper are: econ
1
The categories of this paper are: cs