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arXiv · 0808.2140

Phase diagram of geometric d-wave superconductor Josephson junctions

A. Gumann·N. Schopohl
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Abstract

We show that a constriction-type Josephson junction realized by an epitactic thin film of a d-wave superconductor with an appropriate boundary geometry exhibits intrinsic phase differences between 0 and pi depending on geometric parameters and temperature. Based on microscopic Eilenberger theory, we provide a general derivation of the relation between the change of the free energy of the junction and the current-phase relation. From the change of the free energy, we calculate phase diagrams and discuss transitions driven by geometric parameters and temperature.

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A. Gumann, N. Schopohl. 2009-02-24. Phase diagram of geometric d-wave superconductor Josephson junctions. https://doi.org/10.1103/physrevb.79.144505

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