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arXiv · 0812.1068

In-gap bound states and tunneling conductance of multiband superconductors through a normal/superconductor/superconductor junction

Xiao-Yong Feng·Tai-Kai Ng
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Abstract

The tunneling conductance between a metal and a multiband s-wave superconductor with a thin layer of single-band s-wave superconductor sandwiched in between is examined in this paper. We show that an in-gap peak in conductance curve is found as a result of the formation of in-gap bound state between the single-band and multiband superconductor junctions if the phases of the superconducting order parameters of the multiband superconductor are frustrated. The implication of this result in determining the gap symmetry of the iron-based superconductors is discussed.

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Xiao-Yong Feng, Tai-Kai Ng. 2009-05-05. In-gap bound states and tunneling conductance of multiband superconductors through a normal/superconductor/superconductor junction. https://doi.org/10.1103/physrevb.79.184503

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