Watching magnetic nano ’tornadoes’ in 3D

Scientists have developed a three-dimensional imaging technique to observe complex behaviours in magnets, including fast-moving waves and 'tornadoes' thousands of times thinner than a human hair. We can now investigate the dynamics of new types of systems that could open up new applications we haven't even thought of Claire Donnelly The team, from the Universities of Cambridge and Glasgow in the UK and ETH Zurich and the Paul Scherrer Institute in Switzerland, used their technique to observe how the magnetisation behaves, the first time this has been done in three dimensions. The technique, called time-resolved magnetic laminography, could be used to understand and control the behaviour of new types of magnets for next-generation data storage and processing. The results are reported . Magnets are widely used in applications from data storage to energy production and sensors. In order to understand why magnets behave the way they do, it is important to understand the structure of their magnetisation, and how that structure reacts to changing currents or magnetic fields. "Until now, it hasn't been possible to actually measure how magnets respond to changing magnetic fields in three dimensions," said Dr Claire Donnelly from Cambridge's Cavendish Laboratory, and the study's first author.