2003/04/30 by Steven C. Erwin, I. I. Mazin
Materials Science · Physics and Astronomy · #Iron-based superconductors research #Physics of Superconductivity and Magnetism #Superconductivity in MgB2 and Alloys #cond-mat.mtrl-sci #cond-mat.supr-con
paper · pdf · doi:10.1103/physrevb.68.132505
published as Phys. Rev. B 68, 132505 (2003) · 4 pages, 2 figures, to appear in Phys. Rev. B
arxiv created 2003/09/25 · openalex publication_date 2003/10/07 · arxiv updated 2009/11/30 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The two-gap model for superconductivity in MgB2 predicts that interband impurity scattering should be pair breaking, reducing the critical temperature. This is perhaps the only prediction of the model that has not been confirmed experimentally. It was previously shown theoretically that common substitutional impurities lead to negligible interband scattering---if the lattice is assumed not to distort. Here we report theoretical results showing that certain impurities can indeed produce lattice distortions sufficiently large to create measurable interband scattering. On this basis, we predict that isoelectronic codoping with Al and Na will provide a decisive test of the two-gap model.