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arXiv · 1103.2187

Atomic scale 0-pi transition in a high-Tc superconductor/ferromagnetic-insulator/high-T superconductor Josephson junction

Shiro Kawabata·Yukio Tanaka·Yasuhiro Asano
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Abstract

We study the Josephson transport in a high-Tc superconductor/ferromagnetic-insulator(FI)/high-Tc superconductor numerically. We found the formation of a pi-junction in such systems. More remarkably the ground state of such junction alternates between 0- and pi-states when thickness of FI is increasing by a single atomic layer. We propose an experimental setup for observing the atomic-scale 0-pi transition. Such FI-based pi-junctions can be used to implement highly-coherent quantum bits.

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Shiro Kawabata, Yukio Tanaka, Yasuhiro Asano. 2011-03-11. Atomic scale 0-pi transition in a high-Tc superconductor/ferromagnetic-insulator/high-T superconductor Josephson junction. https://doi.org/10.1016/j.physe.2010.07.038

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