Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Theory of spin accumulation and spin transfer torque in a magnetic
  domain wall   We study spin accumulation and spin transfer torque in a domain wall by
solving the Boltzmann equation with a diffusion approximation. We obtained the
analytical expressions of spin accumulation and spin transfer torque. Both the
adiabatic and the non-adiabatic components of the spin transfer torque
oscillate with the thickness of the domain wall. We show that the oscillation
plays a dominant role in the non-adiabatic torque when the domain wall
thickness is less than the spin-flip length, which is defined by the product of
the Fermi velocity and the spin-flip scattering time.

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The categories of this paper are: astro-ph
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The categories of this paper are: hep-ex
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The categories of this paper are: econ
35
The categories of this paper are: mtrl-th
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The categories of this paper are: hep-th
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The categories of this paper are: nlin
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The categories of this paper are: atom-ph
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The categories of this paper are: nucl-ex
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The categories of this paper are: math
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The categories of this paper are: gr-qc
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The categories of this paper are: physics
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The categories of this paper are: q-bio
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The categories of this paper are: q-alg
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The categories of this paper are: chem-ph
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The categories of this paper are: eess
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The categories of this paper are: supr-con