Electrically induced strong modulation of magnons transport in ultrathin magnetic insulator films

TL;DR

This paper demonstrates that electrical currents can strongly modulate magnon transport in ultrathin yttrium iron garnet films, achieving over 40% modulation efficiency, with high current densities not inducing magnetic instability.

Contribution

It reports nonlinear magnon transport modulation effects in 10 nm thick YIG films using current-biased heavy-metal gates, a significant advancement in controlling magnon conductivity.

Findings

Modulation efficiency exceeds 40% per mA.

High current density does not induce magnetic instability.

Magnon transport saturates at high current densities.

Abstract

Magnon transport through a magnetic insulator can be controlled by current-biased heavy-metal gates that modulate the magnon conductivity via the magnon density. Here, we report nonlinear modulation effects in 10$\,$nm thick yttrium iron garnet (YIG) films. The modulation efficiency is larger than 40\%/mA. The spin transport signal at high DC current density (2.2$\times 10^{11}\,$A/m$^{2}$) saturates for a 400$\,$nm wide Pt gate, which indicates that even at high current levels a magnetic instability cannot be reached in spite of the high magnetic quality of the films.