Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Morphology of epitaxial core-shell nanowires   We analyze the morphological stability against azimuthal, axial, and general
helical perturbations for epitaxial core-shell nanowires in the growth regimes
limited by either surface diffusion or evaporation-condensation surface
kinetics. For both regimes, we find that geometric parameters (i.e., core
radius and shell thickness) play a central role in determining whether the
nanowire remains cylindrical or its shell breaks up into epitaxial islands
similar to those observed during Stranski-Krastanow growth in thin epilayers.
The combination of small cores and rapid growth of the shell emerge as key
ingredients for stable shell growth. Our results provide an explanation for the
different core-shell morphologies reported in the Si-Ge system experimentally,
and also identify a growth-induced intrinsic mechanism for the formation of
helical nanowires.

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The categories of this paper are: bayes-an
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The categories of this paper are: alg-geom
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The categories of this paper are: comp-gas
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The categories of this paper are: math-ph
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The categories of this paper are: acc-phys
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The categories of this paper are: eess
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The categories of this paper are: nucl-ex
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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: ao-sci
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The categories of this paper are: chem-ph
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The categories of this paper are: q-fin
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The categories of this paper are: astro-ph
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The categories of this paper are: physics
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The categories of this paper are: supr-con
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The categories of this paper are: funct-an