Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Universal low-temperature Ohmic contacts for quantum transport in
  transition metal dichalcogenides   Low carrier mobility and high electrical contact resistance are two major
obstacles prohibiting explorations of quantum transport in TMDCs. Here, we
demonstrate an effective method to establish low-temperature Ohmic contacts in
boron nitride encapsulated TMDC devices based on selective etching and
conventional electron-beam evaporation of metal electrodes. This method works
for most extensively studied TMDCs in recent years, including MoS2, MoSe2,
WSe2, WS2, and 2H-MoTe2. Low electrical contact resistance is achieved at 2 K.
All of the few-layer TMDC devices studied show excellent performance with
remarkably improved field-effect mobilities ranging from 2300 cm2/V s to 16000
cm2/V s, as verified by the high carrier mobilities extracted from Hall effect
measurements. Moreover, both high-mobility n-type and p-type TMDC channels can
be realized by simply using appropriate contact metals. Prominent Shubnikov-de
Haas oscillations have been observed and investigated in these high-quality
TMDC devices.

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The categories of this paper are: astro-ph
35
The categories of this paper are: mtrl-th
25
The categories of this paper are: patt-sol
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
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The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
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The categories of this paper are: cmp-lg
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The categories of this paper are: q-fin
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The categories of this paper are: plasm-ph
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The categories of this paper are: hep-th
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The categories of this paper are: funct-an
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The categories of this paper are: nlin
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The categories of this paper are: ao-sci
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The categories of this paper are: alg-geom
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The categories of this paper are: eess