Magnetic skyrmions, topologically stabilized chiral magnetic textures with particle-like properties have so far primarily been studied statically. Here, we experimentally investigate the dynamics of skyrmion ensembles in metallic thin film conduits where they behave as quasi-particle fluids. By exploiting our access to the full trajectories of all fluid particles by means of time-resolved magneto-optical Kerr microscopy, we demonstrate that boundary conditions of skyrmion fluids can be tuned by modulation of the channel geometry. We observe as a function of channel width deviations from classical flow profiles even into the no- or partial-slip regime. Unlike conventional colloids, the skyrmion Hall effect can also introduce transversal flow-asymmetries and even local motion of single skyrmions against the driving force which we explore with particle-based simulations, demonstrating the unique properties of skyrmion liquid flow that uniquely deviates from previously known behavior of other quasi-particles.
@article{arxiv.2403.07397,
title = {Skyrmion flow in periodically modulated channels},
author = {Klaus Raab and Maurice Schmitt and Maarten A. Brems and Jan Rothörl and Fabian Kammerbauer and Sachin Krishnia and Mathias Kläui and Peter Virnau},
journal= {arXiv preprint arXiv:2403.07397},
year = {2024}
}