Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Nonmonotonic inelastic tunneling spectra due to surface spin excitations
  in ferromagnetic junctions   The paper addresses inelastic spin-flip tunneling accompanied by surface spin
excitations (magnons) in ferromagnetic junctions. The inelastic tunneling
current is proportional to the magnon density of states which is
energy-independent for the surface waves and, for this reason, cannot account
for the bias-voltage dependence of the observed inelastic tunneling spectra.
This paper shows that the bias-voltage dependence of the tunneling spectra can
arise from the tunneling matrix elements of the electron-magnon interaction.
These matrix elements are derived from the Coulomb exchange interaction using
the itinerant-electron model of magnon-assisted tunneling. The results for the
inelastic tunneling spectra, based on the nonequilibrium Green's function
calculations, are presented for both parallel and antiparallel magnetizations
in the ferromagnetic leads.

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The categories of this paper are: q-alg
13
The categories of this paper are: quant-ph
33
The categories of this paper are: plasm-ph
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The categories of this paper are: supr-con
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The categories of this paper are: astro-ph
32
The categories of this paper are: atom-ph
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The categories of this paper are: acc-phys
1
The categories of this paper are: cs
3
The categories of this paper are: physics
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The categories of this paper are: adap-org
2
The categories of this paper are: math
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The categories of this paper are: comp-gas
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The categories of this paper are: nucl-th
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The categories of this paper are: mtrl-th
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The categories of this paper are: solv-int
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The categories of this paper are: chem-ph