Breathing modes of confined skyrmions in ultrathin magnetic dots

TL;DR

This paper theoretically investigates the breathing modes of confined magnetic skyrmions in ultrathin ferromagnetic dots, revealing hybridization with spin wave modes and proposing a method for experimental detection.

Contribution

It introduces a micromagnetic simulation study showing how skyrmion breathing modes hybridize with quantized spin wave eigenmodes in ultrathin dots, providing insights into their dynamic response.

Findings

Breathing modes hybridize with spin wave eigenmodes.

Distinct spectral features depend on the magnetic field.

Field dependence enables experimental detection of skyrmions.

Abstract

The dynamics of individual magnetic skyrmions confined in ultrathin film dots is studied theoretically. The systems considered are transition metal ferromagnets possessing perpendicular magnetic anisotropy and particular attention is given to the dynamic response of the skyrmions to perpendicular driving fields. By using micromagnetics simulations, it is shown that breathing modes can hybridize with geometrically-quantized spin wave eigenmodes of the circular dots considered, leading to distinct features in the power spectrum that differ to the behavior expected for uniformly magnetized systems. The field dependence of the breathing modes offers a direct means of detecting and characterizing such skyrmion states in experiment.