Electrically-gated laser-induced spin dynamics in magneto-electric iron garnet at room temperature

TL;DR

This study demonstrates that applying an external electric field can significantly enhance and control laser-induced spin wave excitation in iron garnet films at room temperature, offering new possibilities for magnonics.

Contribution

It introduces an electric gating method to control laser-induced spin dynamics in iron garnet, a novel approach at room temperature with large effects.

Findings

Electric field dramatically increases spin wave excitation efficiency.

Control of spin dynamics via electrical gating at room temperature.

Potential for new magnonics applications using electric control.

Abstract

Ultrafast pump-probe imaging reveals that the efficiency of optical excitation of coherent spins waves in epitaxial iron garnet films can be effectively controlled by an external electric field at room temperature. Although a femtosecond laser pulse alone does not excite any pronounced coherent spin oscillations, an electrical gating with the field of 0.5 MV/m dramatically changes the outcome in a laser-induced launching of spin waves. The effect, demonstrated under room-temperature conditions, is estimated to be orders of magnitude larger than in magnetic van der Waals semiconductors observed at 10 K. This electrical gating of laser-induced spin dynamics enriches opto-magnonics with a new tool and thus opens up a new avenue in fundamental and applied magnonics research.