Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: A Low Profile Tunable Microwave Absorber based on Graphene Sandwich
  Structure and High Impedance Surface   In this paper, a low profile dynamically tunable microwave absorber is
proposed, which consists of high impedance surface (HIS) and graphene sandwich
structure (GSS). We theoretically demonstrate and experimentally verify that
the proposed absorber can provide a dynamically tunable reflection range from
larger than -3dB to less than -30 dB (corresponding to the absorption range
from 50% to 99.9%) at opera-ting frequency of 11.2GHz by external bias voltage.
The entire thickness of this absorber is only 2.8mm, nearly one tenth of
working wavelength. In addition, a modified equivalent circuit model is
proposed to explicate its absorption mechanism. At last, we fabricate a
prototype absorber, and measure its absorption in anechoic chamber. The
experimental results agree well with the full wave simulation results. This
work may provide a reference for design and fabrication of dynamically tunable
microwave absorber based on large-scale graphene and may promote the actual
applications of graphene at microwave frequency.

30
The categories of this paper are: q-alg
29
The categories of this paper are: funct-an
6
The categories of this paper are: astro-ph
37
The categories of this paper are: supr-con
14
The categories of this paper are: math-ph
9
The categories of this paper are: nlin
25
The categories of this paper are: patt-sol
18
The categories of this paper are: econ
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
26
The categories of this paper are: bayes-an
7
The categories of this paper are: hep-th
2
The categories of this paper are: math
28
The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph