Role of Sn impurity on electronic topological transitions in 122 Fe-based superconductors

Haranath Ghosh; Smritijit Sen

doi:10.1016/j.jallcom.2016.03.257

paper

Role of Sn impurity on electronic topological transitions in 122 Fe-based superconductors

arXiv:1603.08772 · doi:10.1016/j.jallcom.2016.03.257

Abstract

We show that only a few percentage of Sn doping at the Ba site on BaFe $_{2}$ As $_{2}$ , can cause electronic topological transition, namely, the Lifshitz transition. A hole like d $_{x y}$ band of Fe undergoes electron like transition due to 4\% Sn doping. Lifshitz transition is found in BaFe $_{2}$ As $_{2}$ system around all the high symmetry points. Our detailed first principles simulation predicts absence of any Lifshitz transition in other 122 family compounds like SrFe $_{2}$ As $_{2}$ , CaFe $_{2}$ As $_{2}$ . This work bears practical significance due to the facts that a few percentage of Sn impurity is in-built in tin-flux grown single crystals method of synthesizing 122 materials and inter-relationship among the Lifshitz transition, magnetism and superconductivity.

22 pages, 9 figures, Accepted by Journal of Alloys and Compounds (2016)