Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Abrupt orthorhombic relaxation in compressively strained ultra-thin
  SrRuO3 films   Lattice structure can dictate electronic and magnetic properties of a
material. Especially, reconstruction at a surface or heterointerface can create
properties that are fundamentally different from those of the corresponding
bulk material. We have investigated the lattice structure on the surface and in
the thin films of epitaxial SrRuO3 with the film thickness up to 22
pseudo-cubic unit cells (u.c.), using the combination of surface sensitive low
energy electron diffraction and bulk sensitive scanning transmission electron
microscopy. Our analysis indicates that, in contrast to many perovskite oxides,
the RuO6 tilt and rotational distortions appear even in single unit cell SrRuO3
thin films on cubic SrTiO3, while the full relaxation to the bulk-like
orthorhombic structure takes 3-4 u.c. from the interface for thicker films. Yet
the TiO6 octahedra of the substrate near the interface with SrRuO3 films show
no sign of distortion, unlike those near the interface with CaRuO3 films. Two
orthogonal in-plane rotated structural domains are identified. These structural
distortions are essential for the nature of the thickness dependent transport
and magnetism in ultrathin films.

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The categories of this paper are: hep-th
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The categories of this paper are: q-bio
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The categories of this paper are: solv-int
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The categories of this paper are: adap-org
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The categories of this paper are: physics
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The categories of this paper are: nucl-ex
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The categories of this paper are: gr-qc
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The categories of this paper are: math
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The categories of this paper are: supr-con
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The categories of this paper are: plasm-ph
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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ph
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The categories of this paper are: stat
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The categories of this paper are: eess
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The categories of this paper are: quant-ph
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The categories of this paper are: math-ph