Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: In-plane Hall effect in c-axis-oriented MgB2 thin films   We have measured the longitudinal resistivity and the Hall resistivity in the
ab-plane of highly c-axis-oriented MgB2 thin films. In the normal state, the
Hall coefficient (R_H) behaves as R_H ~ T with increasing temperature (T) up to
130 K and then deviates from that linear T-dependence at higher temperatures.
The T^2 dependence of the cotangent of the Hall angle is only observed above
130 K. The mixed-state Hall effect reveals no sign anomaly over a wide range of
current densities from 10^2 to 10^4 A/cm^2 and for magnetic fields up to 5 T.

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The categories of this paper are: ao-sci
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The categories of this paper are: solv-int
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: alg-geom
0
The categories of this paper are: hep-ph
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The categories of this paper are: patt-sol
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The categories of this paper are: mtrl-th
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The categories of this paper are: cmp-lg
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The categories of this paper are: quant-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: econ
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The categories of this paper are: hep-th
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The categories of this paper are: hep-ex
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The categories of this paper are: hep-lat
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The categories of this paper are: gr-qc