Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Cross-Sectional Scanning Tunneling Microscopy and Spectroscopy of
  Semimetallic ErAs Nanostructures Embedded in GaAs   The growth and atomic/electronic structure of molecular beam epitaxy
(MBE)-grown ErAs nanoparticles and nanorods embedded within a GaAs matrix are
examined for the first time via cross-sectional scanning tunneling microscopy
(XSTM) and spectroscopy (XSTS). Cross sections enable the interrogation of the
internal structure and are well suited for studying embedded nanostructures.
The early stages of embedded ErAs nanostructure growth are examined via these
techniques and compared with previous cross sectional TEM work. Tunneling
spectroscopy I(V) for both ErAs nanoparticles and nanorods was also performed,
demonstrating that both nanostructures are semimetallic.

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The categories of this paper are: hep-th
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The categories of this paper are: solv-int
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The categories of this paper are: mtrl-th
2
The categories of this paper are: math
33
The categories of this paper are: plasm-ph
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The categories of this paper are: math-ph
10
The categories of this paper are: q-bio
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The categories of this paper are: adap-org
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The categories of this paper are: alg-geom
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The categories of this paper are: patt-sol
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The categories of this paper are: dg-ga
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The categories of this paper are: comp-gas
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The categories of this paper are: cmp-lg
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The categories of this paper are: physics
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The categories of this paper are: nucl-th
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The categories of this paper are: nlin