Metals with many bands at the Fermi level can have different band dependent gaps in the superconducting state. The absence of translational symmetry at an interface can induce interband scattering and modify the superconducting properties. We dicuss the relevance of these effects to recent experiments in MgB2.
@article{arxiv.cond-mat/0103190,
title = {Surface effects in multiband superconductors. Application to MgB$_2$},
author = {E. Bascones and F. Guinea},
journal= {arXiv preprint arXiv:cond-mat/0103190},
year = {2009}
}