The superconductivity is the most charming phenomena in condensed matters, and has been the eternal subject of understanding the mechanism. Needless to say, the study of superconductivity rushed into a new phase when the high-Tc Cu oxides were discovered. Here, the new physics underling the carrier doping to the Mott insulator has been discussed. More recently, the discovery of Fe based superconductors opened a new filed of the superconductivity where the orbital degeneracy playing an important role, so called t2g physics. On the other hand, we know for the long time that f-electron system forming a heavy electron due to the strong mixing between conduction and localized f-electrons undergoes superconductivity. In this field, the discovery of rather high-Tc superconductivity in Pu based compounds again stimulated the extended study.
It seems that the most of crews of the superconductivity are on the
stage. In this talk, we try to overview the characteristics of above
mentioned cases for the exotic superconductivity from an NMR point of
view. We also try to prospect a way of approaching to the new physic on
superconductivity.