Josephson effect in superconducting constrictions with hybrid SF electrodes: peculiar properties determined by the misorientation of magnetizations

TL;DR

This paper investigates how the misorientation angle between magnetizations in ferromagnetic layers affects the Josephson current in SFcFS junctions, revealing significant modifications to the current-phase relation and critical current behavior.

Contribution

It provides a detailed analysis of the impact of magnetization misorientation on Josephson effects in SFcFS junctions, highlighting conditions for current enhancement and phase relation changes.

Findings

The current-phase relation can be radically altered by the misorientation angle.

The harmonic component of the supercurrent can vanish at specific angles.

The critical current can be nonmonotonically dependent on the misorientation angle.

Abstract

Josephson current in SFcFS junctions with arbitrary transparency of the constriction (c) is investigated. The emphasis is done on the analysis of the supercurrent dependencies on the misorientation angle $\theta $ between the in-plane magnetizations of diffusive ferromagnetic layers (F). It is found that the current-phase relation $I(\phi)$ may be radically modified with the $\theta $ variation: the harmonic $I_{1}\sin \phi $ vanishes for definite value of $\theta $ provided for identical orientation of the magnetizations ($\theta =0$) the junction is in the $"\pi"$ state. The Josephson current may exhibit a nonmonotonic dependence on the misorientation angle both for realization of $"0 "$ and $"\pi "$ state at $\theta =0$. We also analyze the effect of exchange field induced enhancement of the critical current which may occur in definite range of $\theta $.