Reply to "Comment on `First-principles calculation of the superconducting transition in MgB2 within the anisotropic Eliashberg formalism'"

TL;DR

This paper defends previous first-principles calculations of superconductivity in MgB2 against criticisms, clarifying that their theoretical results are valid in the clean limit and that Coulomb interactions between sigma and pi states are significant.

Contribution

The authors respond to critiques by clarifying the validity of their calculations and disputing claims about the observability of energy gap variations and Coulomb interaction approximations.

Findings

Their theoretical work remains valid in the clean limit.

Energy gap variations are observable despite scattering effects.

Coulomb repulsion between sigma and pi states is non-negligible.

Abstract

The recent preprint by Mazin et al. [cond-mat/0212417] contains many inappropriate evaluations and/or criticisms on our published work [Phys. Rev. B 66, 020513 (2002) and Nature 418, 758 (2002)]. The preprint [cond-mat/0212417v1] was submitted to Physical Review B as a comment on one of our papers [Phys. Rev. B 66, 020513 (2002)]. In the reviewing process, Mazin et al. have withdrawn many of the statements contained in cond-mat/0212417v1, however two claims remain in their revised manuscript [cond-mat/0212417v3]: (1) the calculated variations of the superconducting energy gap within the sigma- or the pi-bands are not observable in real samples due to scatterings, and (2) the Coulomb repulsion mu(k,k') is negligibly small between sigma- and pi-states and thus should be approximated by a diagonal 2 x 2 matrix in the sigma and pi channels. Here, we point out that the former does not affect the validity of our theoretical work which is for the clean limit, and that the latter is not correct.