Our recent study on the breathing modes of magnetic skyrmions in confined dots has just been published in Physical Review B.
The breathing modes lead to clear signatures in the power spectrum of the magnetic excitations, which are distinct from the usual ferromagnetic resonance-like modes expected in uniformly magnetized dots. We suggest that this might be a useful feature for identifying the presence of skyrmions in ultrathin dots.
Acknowledgements: The authors are grateful to Noah Vanhorne and Nicolas Reyren at the Unité Mixte de Physique CNRS/Thales for stimulating discussions. This work was partially supported by the French National Research Agency (ANR) under contract numbers ANR-11-BS10-0003 (NanoSWITI) and ANR-11-BS10-008 (ESPERADO)