Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Revelation of the role of impurities and conduction electron density in
  the high resolution photoemission study of ferromagnetic hexaborides   We investigate the temperature evolution of the electronic structure of
ferromagnetic CaB$_6$ using ultra-high resolution photoemission spectroscopy;
electronic structure of paramagnetic LaB$_6$ is used as a reference. High
resolution spectra of CaB$_6$ reveal finite density of states at the Fermi
level, $\epsilon_F$ at all the temperatures and evidence of impurity induced
localized features in the vicinity of $\epsilon_F$, which are absent in the
spectra of LaB$_6$. Analysis of the high resolution spectra suggests that
disorder in B-sublattice inducing partial localization in the mobile electrons
and low electron density at $\epsilon_F$ is important to achieve ferromagnetism
in these systems.

14
The categories of this paper are: math-ph
27
The categories of this paper are: comp-gas
13
The categories of this paper are: quant-ph
20
The categories of this paper are: acc-phys
37
The categories of this paper are: supr-con
30
The categories of this paper are: q-alg
17
The categories of this paper are: q-fin
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
33
The categories of this paper are: plasm-ph
36
The categories of this paper are: cmp-lg
18
The categories of this paper are: econ
3
The categories of this paper are: physics
2
The categories of this paper are: math
11
The categories of this paper are: hep-lat
16
The categories of this paper are: stat