Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Large Magnetic-Field-Induced Strains in Ni-Mn-Ga Alloys due to
  Redistribution of Martensite Variants   A polycrystalline and single-crystal samples of near-stoichiometric Ni2MnGa
alloys have been investigated. It was confirmed that martensite short
crystallographic axis (c-axis) is the easy axis of magnetization. The
reversible reorientation of the easy magnetization direction of martensite
samples after 5% compression is found. The same reversible reorientation of the
easy magnetization direction under applied magnetic field occurs in the
single-crystal samples. The field-induced reorientation of the easy
magnetization direction is accompanied with more than 4% of sample's dimension
change. About the same value of the field-induced strains can be obtained for
polycrystalline samples after appropriate thermo-mechanical treatment.

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The categories of this paper are: math-ph
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom
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The categories of this paper are: adap-org
2
The categories of this paper are: math
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The categories of this paper are: nucl-th
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The categories of this paper are: gr-qc
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The categories of this paper are: econ
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The categories of this paper are: nucl-ex
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The categories of this paper are: physics
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The categories of this paper are: comp-gas
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The categories of this paper are: hep-ph
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The categories of this paper are: supr-con
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The categories of this paper are: eess
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The categories of this paper are: q-bio