Oscillations of skyrmion clusters in Co/Pt multilayer nanodots

TL;DR

This study investigates how skyrmion core oscillations in Co/Pt multilayer nanodots depend on the number of skyrmions, revealing a relationship between oscillation frequency, system energy, and skyrmion count.

Contribution

It demonstrates the dependence of skyrmion core oscillation frequency on skyrmion number and total energy in multilayer nanodots, a novel insight into skyrmion dynamics.

Findings

Oscillation frequency varies with skyrmion number.

Oscillation frequency correlates with total system energy.

Coherent damped oscillations observed after current application.

Abstract

In this work we study the oscillations of the skyrmion cores in a multilayer nanodot as a function of the number of skyrmions hosted in the system. When all the skyrmions in the nanodot have the same core radius, and after applying a perpendicular spin-polarized current, a relaxation process takes place towards an equilibrium configuration that is accompanied by coherent damped oscillations of the skyrmion cores, whose frequency depends on the number of skyrmions present in the nanodot. Additionally, we found that the oscillation frequency is directly related to the total energy of the system.