Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Band-filling effect on magnetic anisotropy using a Green's function
  method   We use an analytical model to describe the magnetocrystalline anisotropy
energy (MAE) in solids as a function of band filling. The MAE is evaluated in
second-order perturbation theory, which makes it possible to decompose the MAE
into a sum of transitions between occupied and unoccupied pairs. The model
enables us to characterize the MAE as a sum of contributions from different,
often competing terms. The nitridometalates Li$_{2}$[(Li$_{1-x}$T$_{x}$)N],
with $T$=Mn, Fe, Co, Ni, provide a system where the model is very effective
because atomic like orbital characters are preserved and the decomposition is
fairly clean. Model results are also compared against MAE evaluated directly
from first-principles calculations for this system. Good qualitative agreement
is found.

22
The categories of this paper are: chao-dyn
2
The categories of this paper are: math
32
The categories of this paper are: atom-ph
30
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
28
The categories of this paper are: alg-geom
16
The categories of this paper are: stat
9
The categories of this paper are: nlin
7
The categories of this paper are: hep-th
12
The categories of this paper are: nucl-th
3
The categories of this paper are: physics
37
The categories of this paper are: supr-con
15
The categories of this paper are: nucl-ex
5
The categories of this paper are: gr-qc
27
The categories of this paper are: comp-gas