FMR induced Josephson Current in a Superconductor/Ferromagnet/Superconductor Junction

TL;DR

This paper explores how spin waves induced by ferromagnetic resonance affect the phase dynamics and current-voltage characteristics of a superconductor/ferromagnet/superconductor Josephson junction, revealing a new method to detect spin wave excitation.

Contribution

It introduces an extended RSJ model incorporating FMR-induced spin waves to analyze phase dynamics in SC/FM/SC Josephson junctions, a novel approach in the field.

Findings

Step structures in I-V characteristics at FMR frequencies

Demonstration of spin wave detection via Josephson effect

Extension of the RSJ model to include spin wave excitation

Abstract

We propose the phase dynamics induced by spin waves in a superconductor/ferromagnet/superconductor (SC/FM/SC) Josephson junction. The resistively shunted junction (RSJ) model, which describes the dynamics of superconducting phase difference, is extended to include the spin wave excitation by ferromagnetic resonance (FMR) using the gauge invariant phase difference between two s-wave superconductors. The current-voltage characteristics show step structures when the magnetization in FM is driven by tuning the microwave frequency to FMR in the SC/FM/SC junction. The result presents a new route to observe the spin wave excitation using the Josephson effect.