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arXiv · 0903.1227

Surface Bound States in n-band Systems with Quasiclassical Approach

Yuki Nagai·Nobuhiko Hayashi
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Abstract

We discuss the tunneling spectroscopy at a surface in multi-band systems such as Fe-based superconductors with the use of the quasiclassical approach. We extend the single-band method by Matsumoto and Shiba [J. Phys. Soc. Jpn. 64, 1703 (1995)] into $n$-band systems ($n \geq 2$). We show that the appearance condition of the zero-bias conductance peak does not depend on details of the pair-potential anisotropy, but it depends on details of the normal state properties in the case of fully-gapped superconductors. The surface density of states in a two-band superconductor is presented as a simplest application. The quasiclassical approach enables us to calculate readily the surface-angular dependence of the tunneling spectroscopy.

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Yuki Nagai, Nobuhiko Hayashi. 2009-03-12. Surface Bound States in n-band Systems with Quasiclassical Approach. https://doi.org/10.1103/physrevb.79.224508

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