Josephson diode effect derived from short-range coherent coupling

TL;DR

This paper demonstrates a new Josephson diode effect in coupled Josephson junctions, where non-local control of the effect is achieved through phase differences, revealing symmetry breaking via coherent coupling.

Contribution

It introduces a novel superconducting diode effect in coupled JJs controlled non-locally, highlighting symmetry breaking through short-range coherent coupling.

Findings

Superconducting diode effect observed in coupled JJs.

Non-local control of the diode effect via phase difference.

Symmetry breaking achieved through coherent coupling.

Abstract

Superconducting devices with broken time-reversal and spatial-inversion symmetries can exhibit novel superconducting phenomena. The observation of superconducting diode effects, which is applicable for dissipationless rectification, provides information on the breaking of such symmetries. We experimentally study a Josephson junction (JJ) coupled to another adjacent JJ as a new system exhibiting the superconducting diode effect. We demonstrate that the observed superconducting diode effect can be controlled non-locally based on the phase difference with the adjacent JJ. These results indicate that the time-reversal and spatial-inversion symmetries of a JJ are broken by the coherent coupling to an adjacent JJ, and this enables the engineering of novel superconducting phenomena mediated by coherent coupling among JJs and development of their applications for superconducting diode devices.