Imaging breakthrough reveals magnets’ internal patterns

A new imaging technique has helped scientists make a breakthrough in how they visualise the directions of magnetisation inside an object. Magnets play a vital role in everyday life, are used in everything from hard drives to energy production, and scientists have already been able to study the structure of thin films of magnetic materials. However, imaging the inner structure of thicker forms of magnets had remained an experimental challenge until now. A better understanding of magnets could contribute to the creation of better motors, more efficient energy production, and hard drives capable of holding more data. In a new paper published in the journal Nature , scientists based in Scotland and Switzerland describe how they have used tomography and high energy x-rays, combined with a novel reconstruction algorithm, to peer inside and reconstruct the magnetic structure of a micrometre-sized 'pillar' of gadolinium-cobalt magnetic material for the first time. The scientists, from the University of Glasgow and the Paul Scherrer Institute and the ETH Zurich in Switzerland, observed complex internal magnetic patterns and quickly realised that they consisted of tangled fundamental magnetic structures. They were able to see 'domains', or regions of homogenous magnetisation, and 'domain walls', the boundaries separating two different domains.