Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Ambipolar Graphene Field Effect Transistors by Local Metal Side Gates   We demonstrate ambipolar graphene field effect transistors individually
controlled by local metal side gates. The side gated field effect can have
on/off ratio comparable with that of the global back gate, and can be tuned in
a large range by the back gate and/or a second side gate. We also find that the
side gated field effect is significantly stronger by electrically floating the
back gate compared to grounding the back gate, consistent with the finding from
electrostatic simulation.

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The categories of this paper are: q-alg
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The categories of this paper are: comp-gas
16
The categories of this paper are: stat
37
The categories of this paper are: supr-con
1
The categories of this paper are: cs
18
The categories of this paper are: econ
23
The categories of this paper are: solv-int
17
The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
24
The categories of this paper are: dg-ga
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The categories of this paper are: atom-ph
22
The categories of this paper are: chao-dyn
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The categories of this paper are: hep-ex
25
The categories of this paper are: patt-sol
13
The categories of this paper are: quant-ph
7
The categories of this paper are: hep-th