In microscale magnetic systems at nonzero temperatures, the continuous excitation by extremely
small thermal fluctuations often gives rise to dynamics on much larger scales. These multiscale
dynamics, spanning up to 9 orders of magnitude, make the study of thermally active systems very
challenging.
In this project, we will address outstanding research questions in systems where thermal
fluctuations give rise to complex dynamics. Within three European collaborations with leading
groups, we will investigate three different systems that are at the forefront of current research.
1. Magnetic bubbles that can become information carriers in future computer memories, but
whose accurate control is impeded by thermal effects on their motion.
2. Large frustrated arrays of nanoscale magnets that do not have a magnetisation state that is
favourable for each individual magnet, which results in unexplored moving magnetic patterns at
nonzero temperature.
3. Interacting magnetic nanoparticles that are important for tomorrow’s biomedical applications,
but are difficult to characterise because current models do not account for the interplay between
their interactions and thermal fluctuations.
We will overcome the challenge of the scale difference between the thermal fluctuations and the
magnetisation dynamics by using a new approach that improves the simulation speed by a factor
twenty, for the first time enabling the extensive micromagnetic study of such systems.