Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Fermi surface origin of the interrelationship between magnetocrystalline
  anisotropy and compositional order in transitional metal alloys   Recently, we outlined a scheme to investigate the effects of compositional
order on the magnetocrystalline anisotropy of alloys from a first-principles
electronic structure point of view \{Phys. Rev. Lett. {\bf 83}, 5369 (1999)\}
and showed that compositional order enhances the magnitude of
magnetocrystalline anisotropy energy (MAE) of Co$_{0.5}$Pt$_{0.5}$ alloy by
some two orders of magnitude as well as affecting the equilibrium magnetization
direction. Here we describe our scheme in detail and present an in-depth study
of the effect by demonstrating its Fermi surface origin. In
Co$_{0.25}$Pt$_{0.75}$ alloy we find that the perfect $ L1_2 $ structure has a
very small MAE whereas imposition of directional order enhances the MAE by two
orders of magnitude. We also present the effect of lattice distortion
(tetragonalization) on the MAE on the same footing and find that in the
Co$_{0.5}$Pt$_{0.5}$ alloy it accounts for only about 20% of the observed MAE,
thus confirming that compositional order is the major player in the enhancement
of MAE. We also examine the directional chemical order that can be produced by
magnetic annealing within the same framework. We extract a Fermi surface
mechanism for the effect in an explicit study of permalloy. Finally, we propose
that the Fermi surface plays a major role in the strong coupling between
magnetocrystalline anisotropy and compositional order in many magnetic alloys.

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The categories of this paper are: mtrl-th
19
The categories of this paper are: eess
7
The categories of this paper are: hep-th
27
The categories of this paper are: comp-gas
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The categories of this paper are: bayes-an
30
The categories of this paper are: q-alg
5
The categories of this paper are: gr-qc
36
The categories of this paper are: cmp-lg
1
The categories of this paper are: cs
33
The categories of this paper are: plasm-ph
20
The categories of this paper are: acc-phys
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
16
The categories of this paper are: stat
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin