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Discrete-Lattice Model for Surface Bound States and Tunneling in d-Wave Superconductors

M. B. Walker·P. Pairor
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Abstract

Surface bound states in a discrete-lattice model of a $d_{x^2 - y^2}$ cuprate superconductor are shown to be, in general, coherent superpositions of an incoming excitation and more than one outgoing excitation, and a simple graphical construction based on a surface Brillouin zone is developed to describe their nature. In addition, a momentum-dependent lifetime contribution to the width of these bound states as observed in tunneling experiments is derived and elucidated in physical terms.

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M. B. Walker, P. Pairor. 1998-03-06. Discrete-Lattice Model for Surface Bound States and Tunneling in d-Wave Superconductors. https://doi.org/10.1103/physrevb.59.1421

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