Mossbauer Spectroscopy Determination of iron foreign phases in the Superconducting Systems; RAsFeO1-x, RAsFeO1-xFx and Sr1-xKxFe2As2

I. Nowik, I. Felner

The recently discovered superconducting - spin density wave materials, containing Fe and As, have raised huge interest. However most materials prepared to date, suffer from a varyi…