Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Enhanced annealing, high Curie temperature and low-voltage gating in
  (Ga,Mn)As: A surface oxide control study   (Ga,Mn)As and related diluted magnetic semiconductors play a major role in
spintronics research because of their potential to combine ferromagnetism and
semiconducting properties in one physical system. Ferromagnetism requires
~1-10% of substitutional Mn_Ga. Unintentional defects formed during growth at
these high dopings significantly suppress the Curie temperature. We present
experiments in which by etching the (Ga,Mn)As surface oxide we achieve a
dramatic reduction of annealing times necessary to optimize the ferromagnetic
film after growth, and report Curie temperature of 180 K at approximately 8% of
Mn_Ga. Our study elucidates the mechanism controlling the removal of the most
detrimental, interstitial Mn defect. The limits and utility of electrical
gating of the highly-doped (Ga,Mn)As semiconductor are not yet established; so
far electric-field effects have been demonstrated on magnetization with tens of
Volts applied on a top-gate, field effect transistor structure. In the second
part of the paper we present a back-gate, n-GaAs/AlAs/GaMnAs transistor
operating at a few Volts. Inspired by the etching study of (Ga,Mn)As films we
apply the oxide-etching/re-oxidation procedure to reduce the thickness (arial
density of carriers) of the (Ga,Mn)As and observe a large enhancement of the
gating efficiency. We report gatable spintronic characteristics on a series of
anisotropic magnetoresistance measurements.

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The categories of this paper are: bayes-an
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The categories of this paper are: astro-ph
0
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: econ
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The categories of this paper are: alg-geom
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The categories of this paper are: nucl-th
2
The categories of this paper are: math
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The categories of this paper are: chao-dyn
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The categories of this paper are: dg-ga
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The categories of this paper are: patt-sol
3
The categories of this paper are: physics
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The categories of this paper are: quant-ph
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The categories of this paper are: solv-int
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The categories of this paper are: nucl-ex
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The categories of this paper are: acc-phys