Researchers spot homochiral antiferromagnetic merons, antimerons and bimerons in synthetic antiferromagnets

Researchers from Johannes Gutenberg-University Mainz, ALBA Synchrotron Light Facility and Tohoku University have identified quasiparticles called merons in a synthetic antiferromagnet for the first time, which could lead to new concepts for spintronics devices.

The spintronics field is still rather nascent as research is ongoing. Recent research has focused on structures called skyrmions as potential building blocks. These structures are quasiparticles made up of numerous electron spins and can be thought of as two-dimensional whirls (or “spin textures”) within a material. Skyrmions exist in many magnetic materials, including cobalt–iron–silicon and the manganese–silicide thin films in which they were first discovered. They are attractive spintronics candidates because they are robust to external perturbations, making them particularly stable for storing and processing the information they contain. At just tens of nanometres across, they are also much smaller than the magnetic domains used to encode data in today’s disk drives, making them ideal for future data storage technologies such as “racetrack” memories. Like skyrmions, merons are made up of numerous individual spins. Unlike them, their stray magnetic fields are miniscule, which would facilitate ultrafast operations and even higher information storage densities within a device. Until now, however, merons have only been observed in natural antiferromagnets, where they have proved difficult to analyze and manipulate.