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arXiv · 2111.05340

Symmetry conditions for the superconducting diode effect in chiral superconductors

Bastian Zinkl·Keita Hamamoto·Manfred Sigrist
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Abstract

We analyze the presence of non-reciprocal critical currents, the so-called superconducting diode effect, in chiral superconductors within a generalized Ginzburg-Landau framework. After deriving its key symmetry conditions we illustrate the basic mechanism for two examples, the critical current in a thin film and a Josephson junction. The appearance of spontaneous edge currents and the energy bias for the formation of Josephson vortices play an essential part in establishing a splitting of the critical currents running in opposite directions. Eventually, this allows us to interpret a superconducting diode effect observed in the 3-Kelvin phase of Sr$_2$RuO$_4$ as evidence for spontaneously broken time-reversal symmetry in the superconducting phase.

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Bastian Zinkl, Keita Hamamoto, Manfred Sigrist. 2021-11-09. Symmetry conditions for the superconducting diode effect in chiral superconductors. https://doi.org/10.1103/physrevresearch.4.033167

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