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Quartett formation at (100)/(110)-interfaces of d-wave superconductors

A. A. Aligia·A. P. Kampf·J. Mannhart
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Abstract

Across a faceted (100)/(110) interface between two d-wave-superconductors the structure of the superconducting order parameter leads to an alternating sign of the local Josephson coupling. Describing the Cooper pair motion along and across the interface by a one-dimensional boson lattice model, we show that a small attractive interaction between the bosons boosts boson binding at the interface -- a phenomenon, which is intimately tied to the staggered sequence of 0- and Pi-junction contacts along the interface. We connect this finding to the recently observed h/4e oscillations in (100)/(110) SQUIDS of cuprate superconductors.

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A. A. Aligia, A. P. Kampf, J. Mannhart. 2004-10-15. Quartett formation at (100)/(110)-interfaces of d-wave superconductors. https://doi.org/10.1103/physrevlett.94.247004

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