Phase dynamics of tunnel Al-based ferromagnetic Josephson junctions

TL;DR

This study investigates the phase dynamics of aluminum-based ferromagnetic Josephson junctions, revealing phase diffusion processes and demonstrating their compatibility with qubit architectures without detrimental effects.

Contribution

It provides experimental evidence that ferromagnetic barriers do not impair the phase dynamics of Al tunnel JJs, supporting their integration into quantum circuits.

Findings

Evidence of phase diffusion in ferromagnetic JJs

Ferromagnetic barriers do not significantly affect junction performance

Supports inclusion of ferromagnetic JJs in qubit designs

Abstract

By measuring the current-voltage characteristics and the switching current distributions as a function of temperature, we have investigated the phase dynamics of Al tunnel ferromagnetic Josephson junctions (JJs), designed to fall in the typical range of parameters of state-of-the-art transmons, providing evidence of phase diffusion processes. The comparison with the experimental outcomes on non-magnetic JJs with nominally the same electrodynamical parameters demonstrates that the introduction of ferromagnetic barriers does not cause any sizeable detrimental effect, and supports the notion of including tunnel ferromagnetic JJs in qubit architectures.