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arXiv · 0801.0515

Fabrication and Characterization of Short Josephson Junctions with Stepped Ferromagnetic Barrier

Uthayasankaran Peralagu·Martin Weides
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Abstract

We present novel low-T_c superconductor-insulator-ferromagnet-superconductor (SIFS) Josephson junctions with planar and stepped ferromagnetic interlayer. We optimized the fabrication process to set a step in the ferromagnetic layer thickness. Depending on the thickness of the ferromagnetic layer the ground state of the SIFS junction has a phase drop of either 0 or pi. So-called 0-pi Josephson junctions, in which 0 and pi ground states compete with each other, were obtained. These stepped junctions may have a double degenerate ground state, corresponding to a vortex of supercurrent circulating clock- or counterclockwise and creating a magnetic flux which carries a fraction of the magnetic flux quantum Φ_0. Here, we limit the presentation to static properties of short junctions.

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Uthayasankaran Peralagu, Martin Weides. 2008-01-18. Fabrication and Characterization of Short Josephson Junctions with Stepped Ferromagnetic Barrier. https://arxiv.org/abs/0801.0515

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