Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Effects of Resonant Tunneling on Magnetoresistance through a Q
  uantum Dot   The effect of resonant tunneling on magnetoresistance (MR) is studied
theoretically in a double junction system. We have found that the ratio of the
MR of the resonant peak current is reduced more than that of the single
junction, whereas that of the valley current is enhanced depending on the
change of the discrete energy-level under the change of magnetic field. We also
found that the peak current-valley current (PV) ratio decreases when the
junction conductance increases.

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The categories of this paper are: q-bio
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The categories of this paper are: astro-ph
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The categories of this paper are: bayes-an
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The categories of this paper are: acc-phys
19
The categories of this paper are: eess
1
The categories of this paper are: cs
27
The categories of this paper are: comp-gas
21
The categories of this paper are: adap-org
8
The categories of this paper are: hep-ex
22
The categories of this paper are: chao-dyn
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-ex
24
The categories of this paper are: dg-ga
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The categories of this paper are: chem-ph
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The categories of this paper are: econ
11
The categories of this paper are: hep-lat