English

Nonmagnetic impurity effects in MgB$_{2}$

Superconductivity 2009-11-10 v1 Materials Science

Abstract

We study nonmagnetic impurity effects in MgB2_{2} using the quasiclassical equations of superconductivity for a weak-coupling two-band model. Parameters in the model are fixed so as to reproduce experiments on MgB2_{2} as closely as possible. The quasiparticle density of states and the specific heat are calculated for various values of the interband impurity scattering. The density of states changes gradually from a two-gap structure into the conventional single-gap structure as the interband scattering increases. It is found that the excitation threshold is not a monotonic function of the interband scattering. Calculated results for the specific heat are in good agreements with experiments on samples after irradiation.

Keywords

Cite

@article{arxiv.cond-mat/0401410,
  title  = {Nonmagnetic impurity effects in MgB$_{2}$},
  author = {Koichi Watanabe and Takafumi Kita},
  journal= {arXiv preprint arXiv:cond-mat/0401410},
  year   = {2009}
}