Reply to Comment on "Violation of Anderson's Theorem for the sign-reversing s-wave state of Iron-Pnictide Superconductors" [arXiv:1012.0414] by Y. Bang

TL;DR

This paper defends the correct use of the T-matrix approximation in studying impurity effects in iron pnictides, arguing that Bang's proposed replacement breaks perturbation theory and is incorrect.

Contribution

It clarifies the proper application of the T-matrix approximation in impurity studies of iron pnictides, countering Bang's erroneous substitution.

Findings

T-matrix approximation is valid for impurity effects in iron pnictides

Bang's replacement T-I breaks perturbation theory

Correct calculation supports previous impurity effect results

Abstract

We explain that the study of impurity effect in iron pnictides are correctly calculated based on the T-matrix approximation, contrary to the Comment by Bang. The replacement T with T-I proposed by Bang breaks the perturbation theory and is therefore erroneous.