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arXiv · 2002.07552

Josephson junction based on highly disordered superconductor/low-resistive normal metal bilayer

Abstract

We calculate current-phase relation (CPR) of a SN-S-SN Josephson junction based on a variable thickness SN bilayer composed of highly disordered superconductor (S) and low-resistive normal metal (N) with proximity induced superconductivity. In case when the thickness of S,N layers and length of S constriction is about of superconducting coherence length the CPR is single-valued, could be close to sinusoidal one and the product $I_cR_n$ can reach $\Delta(0)/2|e|$ ($I_c$ is the critical current of the junction, $R_n$ is its normal-state resistance, $\Delta(0)$ is the superconductor gap of single S layer at zero temperature). We argue that the normal layer should provide good heat removal from S constriction and there is range of parameters when current-voltage characteristic is not hysteretic and $I_cR_n$ is relatively large.

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P. M. Marychev, D. Yu. Vodolazov. 2020-02-18. Josephson junction based on highly disordered superconductor/low-resistive normal metal bilayer. https://arxiv.org/abs/2002.07552

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