Realization of 0 - $\pi$ states in SFIS Josephson junctions. The role of spin-orbit interaction and lattice impurities

TL;DR

This paper explores superconductor-ferromagnetic insulator-superconductor (SFIS) Josephson junctions, focusing on how spin-orbit interaction and impurities influence the 0-$ extpi$ phase transition, with potential applications in quantum circuits.

Contribution

It demonstrates the controllable transition between 0 and $ extpi$ phases in SFIS junctions, highlighting the effects of impurities and spin-orbit coupling on their transport properties.

Findings

Transition between 0 and $ extpi$ phases can be tuned by impurities and spin-orbit interaction.

Stable $ extpi$ junctions are achievable across the entire temperature range.

Impurities and spin mixing mechanisms significantly affect the critical current behavior.

Abstract

Josephson devices with ferromagnetic barriers have been widely studied. Much less is known when the ferromagnetic layer is insulating. In this manuscript we investigate the transport properties of superconductor-ferromagnetic insulator-superconductor (SFIS) junctions with particular attention to the temperature behavior of the critical current, that may be used as a fingerprint of the junction. We investigate the specific role of impurities as well as of possible spin mixing mechanisms, due to the spin orbit coupling. Transition between the 0 and the $\pi$ phases can be properly tuned, thus achieving stable $\pi$ junctions over the whole temperature range, that may be possibly employed in superconducting quantum circuits.