All optical control of bubble and skyrmion breathing

TL;DR

This paper demonstrates all-optical control of the breathing modes of bubbles and skyrmions in ferrimagnetic multilayers, enabling precise tuning of their dynamics for potential spintronic applications.

Contribution

It introduces a double excitation optical scheme to control the amplitude and phase of skyrmion and bubble breathing modes, revealing insights into their dynamics.

Findings

Ultrafast laser pulses induce periodic breathing modes.

Double excitation scheme allows phase and amplitude control.

Size of spin objects influences their dynamic response.

Abstract

Controlling the dynamics of topologically protected spin objects by all optical means promises enormous potential for future spintronic applications. Excitation of bubbles and skyrmions in ferrimagnetic [Fe(0.35 nm)/Gd(0.40 nm)]$_{160}$ multilayers by ultrashort laser pulses leads to a periodic modulation of the core diameter of these spin objects, the so-called breathing mode. We demonstrate versatile amplitude and phase control of this breathing using a double excitation scheme, where the observed dynamics is controlled by the excitation delay. We gain insight into both the time scale on which the breathing mode is launched and the role of the spin object size on the dynamics. Our results demonstrate that ultrafast optical excitation allows for precise tuning of the spin dynamics of trivial and non-trivial spin objects, showing a possible control strategy in device applications.