Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Strain-activated structural anisotropy in BaFe2As2   High-resolution single crystal neutron diffraction measurements are presented
probing the magnetostructural response to uniaxial pressure in the iron
pnictide parent system BaFe2As2. Scattering data reveal a strain-activated,
anisotropic broadening of nuclear Bragg reflections, which increases upon
cooling below the resolvable onset of global orthorhombicity. This anisotropy
in lattice coherence continues to diverge until a lower temperature scale---the
first-order onset of antiferromagnetism---is reached. Our data suggest that
antiferromagnetism and strong magnetoelastic coupling drive the
strain-activated lattice response in this material and that the development of
anisotropic lattice coherence under strain is the physical origin for the
anomalous nematic anisotropy in this compound.

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The categories of this paper are: adap-org
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The categories of this paper are: eess
1
The categories of this paper are: cs
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
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The categories of this paper are: q-fin
33
The categories of this paper are: plasm-ph
2
The categories of this paper are: math
34
The categories of this paper are: chem-ph
6
The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
10
The categories of this paper are: q-bio
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The categories of this paper are: patt-sol
32
The categories of this paper are: atom-ph