Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: The Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ superconducting four-gap temperature
  evolution: a multi-band Chebyshev-BdG approach   We generalize the Chebyshev-Bogoliubov-deGennes method to treat multi-band
systems to address the temperature dependence of the superconducting (SC) gaps
of iron based superconductors. Four SC gaps associated with different electron
and hole pockets of optimally doped Ba$_{0.6}$K$_{0.4}$Fe$_2$As$_2$ were
clearly identified by angle resolved photo-emission spectroscopy. The few
approaches that reproduces with success this gap structure are based on
strong-coupling theories and required many adjustable parameters. We show that
an approach with a redistribution of electron population between the hole and
electron pockets $\nu$ with evolving temperature reproduces the different
coupling ratios $2\Delta^{\nu}(0)/k_{\rm B} T_c$ in these materials. We define
the values that fit the four zero temperature gaps $\Delta^{\nu}(0)$ and after
that all $\Delta^{\nu}(T)$ is obtained without any additional parameter.

11
The categories of this paper are: hep-lat
20
The categories of this paper are: acc-phys
2
The categories of this paper are: math
6
The categories of this paper are: astro-ph
22
The categories of this paper are: chao-dyn
32
The categories of this paper are: atom-ph
29
The categories of this paper are: funct-an
15
The categories of this paper are: nucl-ex
26
The categories of this paper are: bayes-an
23
The categories of this paper are: solv-int
25
The categories of this paper are: patt-sol
21
The categories of this paper are: adap-org
27
The categories of this paper are: comp-gas
24
The categories of this paper are: dg-ga
19
The categories of this paper are: eess
28
The categories of this paper are: alg-geom