Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Voltage-tunable ferromagnetism in semimagnetic quantum dots with few
  particles: magnetic polarons and electrical capacitance   Magnetic semiconductor quantum dots with a few carriers represent an
interesting model system where ferromagnetic interactions can be tuned by
voltage. By designing the geometry of a doped quantum dot, one can tailor the
anisotropic quantum states of magnetic polarons. The strong anisotropy of
magnetic polaron states in disk-like quantum dots with holes comes from the
spin splitting in the valence band. The binding energy and spontaneous
magnetization of quantum dots oscillate with the number of particles and
reflect the shell structure. Due to the Coulomb interaction, the maximum
binding energy and spin polarization of magnetic polarons occur in the regime
of Hund's rule when the total spin of holes in a quantum dot is maximum. With
increasing number of particles in a quantum dot and for certain orbital
configurations, the ferromagnetic state becomes especially stable or may have
broken symmetry. In quantum dots with a strong ferromagnetic interaction, the
ground state can undergo a transition from a magnetic to a nonmagnetic state
with increasing temperature or decreasing exchange interaction. The
characteristic temperature and fluctuations of magnetic polarons depend on the
binding energy and degeneracy of the shell. The capacitance spectra of magnetic
quantum dots with few particles reveal the formation of polaron states.

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The categories of this paper are: hep-lat
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The categories of this paper are: hep-ex
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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: quant-ph
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The categories of this paper are: chao-dyn
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The categories of this paper are: eess
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The categories of this paper are: ao-sci
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The categories of this paper are: q-alg
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The categories of this paper are: acc-phys
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The categories of this paper are: q-fin
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The categories of this paper are: adap-org
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The categories of this paper are: patt-sol
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The categories of this paper are: stat
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The categories of this paper are: solv-int
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The categories of this paper are: q-bio