Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Effects of isoelectronic Ru substitution at the Fe site on the energy
  gaps of optimally F-doped SmFeAsO   We studied the effects of isoelectronic Ru substitution at the Fe site on the
energy gaps of optimally F-doped SmFeAsO by means of point-contact Andreev
reflection spectroscopy. The results show that the
SmFe_{1-x}Ru_{x}AsO_{0.85}F_{0.15} system keeps a multigap character at least
up to x=0.50, and that the gap amplitudes Delta_1 and Delta_2 scale almost
linearly with the local critical temperature TcA. The gap ratios 2Delta_i/(kB
Tc) remain approximately constant only as long as Tc > 30 K, but increase
dramatically when Tc decreases further. This trend seems to be common to many
Fe-based superconductors, irrespective of their family. Based on
first-principle calculations of the bandstructure and of the density of states
projected on the different bands, we show that this trend, as well as the Tc
dependence of the gaps and the reduction of Tc upon Ru doping, can be explained
within an effective three-band Eliashberg model as being due to a suppression
of the superfluid density at finite temperature that, in turns, modifies the
temperature dependence of the characteristic spin-fluctuation energy.

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The categories of this paper are: q-alg
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas
36
The categories of this paper are: cmp-lg
2
The categories of this paper are: math
7
The categories of this paper are: hep-th
37
The categories of this paper are: supr-con
19
The categories of this paper are: eess
33
The categories of this paper are: plasm-ph
31
The categories of this paper are: ao-sci
9
The categories of this paper are: nlin
29
The categories of this paper are: funct-an
16
The categories of this paper are: stat
22
The categories of this paper are: chao-dyn
10
The categories of this paper are: q-bio
15
The categories of this paper are: nucl-ex