Theory of Andreev reflection in junctions with iron-based High-$T_c$ superconductors

Abstract

We construct a theory for low-energy quantum transport in normal$\mid$superconductor junctions involving the recently discovered iron-based high-$T_c$ superconductors. We properly take into account both Andreev bound surface states and the complex Fermi surface topology in our approach, and investigate the signatures of the possible order parameter symmetries for the FeAs-lattice. Our results could be helpful in determining the symmetry of the superconducting state in the iron-pnicitide superconductors.