Triplet Josephson effect with magnetic feedback

TL;DR

This paper investigates how magnetic feedback in a superconductor-ferromagnet junction influences the AC Josephson effect, revealing complex behaviors like double-periodicity and loss of periodicity depending on frequency.

Contribution

It introduces a model showing how magnetic feedback alters the Josephson current-phase relation, leading to novel dynamic phenomena in superconductor-ferromagnet systems.

Findings

Double-periodic current-phase relation at low and high frequencies

Loss of periodicity in intermediate frequency range

Magnetic feedback significantly modifies junction dynamics

Abstract

We study AC Josephson effect in a superconductor-ferromagnet heterostructure with a variable magnetic configuration. The system supports triplet proximity correlations whose dynamics is coupled to the magnetic dynamics. This feedback dramatically modifies the behavior of the junction. The current-phase relation becomes double-periodic at both very low and high Josephson frequencies $\omega_J$. At intermediate frequencies, the periodicity in $\omega_J t$ may be lost.