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arXiv · 1905.09672

Devil's staircase structures in $\varphi_{0}$ junction

M. Nashaat·Yu. M. Shukrinov·A. Y. Ellithi·Th. M. El Sherbini
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Abstract

The superconductor-ferromagnet-superconductor $\varphi_{0}$ junction provides a direct coupling between Josephson phase and magnetic moment of ferromagnetic barrier. We demonstrate an appearance of additional fractional subharmonic steps in the IV-characteristics of $\varphi_{0}$ junction under external electromagnetic radiation due to spin-orbit coupling. An origin of subharmonic steps is related to the locking of magnetic moment precession to the Josephson oscillations. We prove that the positions of those steps follow a continued fraction algorithm.

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M. Nashaat, Yu. M. Shukrinov, A. Y. Ellithi, Th. M. El Sherbini. 2019-05-23. Devil's staircase structures in $\varphi_{0}$ junction. https://arxiv.org/abs/1905.09672

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