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arXiv · 2106.03575

A phenomenological theory of superconductor diodes

James Jun He·Yukio Tanaka·Naoto Nagaosa
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Abstract

We study theoretically the superconductor diodes, where the magnitude of the critical current changes as the direction is reversed, in terms of a generalized Ginzburg-Landau model with the higher-order terms in the momentum of the order parameter. This theory is applied to Rashba spin-orbit coupled systems, where analytical relations between the nonreciprocal critical currents and the system parameters are achieved. Numerical calculations with mean-field theory are also obtained to study broader parameter regions. These results offer a rather general description and design principles of superconductor diodes.

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James Jun He, Yukio Tanaka, Naoto Nagaosa. 2021-06-07. A phenomenological theory of superconductor diodes. https://doi.org/10.1088/1367-2630/ac6766

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