EN
In the present paper we report a summary of the infrared studies
on the multi-band Ba(Fe1-xCox)2As2 pnictide system, devoted
to the detection of superconducting gaps in the terahertz
region. Generally, results obtained in the superconducting
state indicate the presence of two gaps, but univocal results
have not been obtained so far. We show that all the literature
gap values of the Ba(Fe1-xCox)2As2 system, when put
together as a function of Tc, show a tendency to cluster along
two main curves, thus allowing to describe the seemingly contradictory
reports into a unified perspective. Below a temperature
around 20 K, the sizes of the two gaps as a function of
Tc seem to have a BCS-like linear behavior, but with different
slopes. In particular, the Δ/kBTc ratio is compatible with the
weak-coupling BCS prediction (1.76) for the large gap, while
it is close to 1 for the small gap. For Tc above 20 K, a clear
supra-linear behavior is observed for the large gap. Although
not so clear, such a tendency is also observable for the small
gap.