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

TL;DR

This paper demonstrates that Mossbauer Spectroscopy effectively quantifies foreign Fe-As phases in superconducting and spin density wave materials, ensuring accurate interpretation of their properties.

Contribution

It introduces Mossbauer Spectroscopy as a reliable method to detect and measure foreign phases in Fe-based superconductors and SDW materials.

Findings

Mossbauer Spectroscopy can distinguish Fe-As foreign phases.

Foreign phase content varies among samples from different labs.

The method provides a straightforward way to assess sample purity.

Abstract

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 varying degree of content of foreign Fe-As phases, Fe2As, FeAs2 and FeAs, which can lead to wrong conclusions concerning the properties of these materials. We show here that Mossbauer Spectroscopy is able to determine quite easily the relative content of the foreign phases. This procedure is demonstrated by a study of seven samples of superconducting or spin density wave materials, prepared in three different laboratories.