Nanoscale chiral magnetic skyrmions have been observed at room temperature for the first time. This is an important experimental breakthrough in the burgeoning field of spintronics, or spin-based electronics, which studies the role of the electron spin in solid state physics. Skyrmions resemble small magnetic vortices and can occur in many materials. Spintronics-based devices can enable non-volatile power efficient functions, like in MRAMs (Magnetic Random Access Memories), as they do not need an electric current to retain their "spin" or magnetic state. Nanoscale spintronics devices could in principle be smaller, faster, more robust and energy efficient than current technologies for data storage.
Scientists from The University of Manchester, the CNRS/Thales laboratory in France, and the Paul Scherrer Institut in Switzerland, in the context of the MAGicSky EU project, have designed cobalt-based multi-layered thin films in which the cobalt layer is sandwiched between two heavy metals. Using a magnetisation-sensitive scanning X-ray transmission microscopy technique, they imaged small magnetic domains at very low fields in these multilayers. The study of their behaviour in a perpendicular magnetic field allows them to conclude that they are actually tiny magnetic skyrmions stabilised by chiral interactions. This discovery of stable sub-100 nm individual skyrmions at room temperature in a technologically relevant material opens the way for device applications in the near future that could revolutionise the data storage industry.
- The next 3 years are critical for producing the first proof-of-principle novel magnetic data storage device based on skyrmion technology.
- In order to be able to observe tiny magnetic skyrmions on very small nanostructures, we used large facilities called synchrotrons that can produce specialised X-rays for imaging. Think about it as taking an X-ray of your hand, or some other object, only that the object is a billion times smaller!
- A magnetic skyrmion has a size from 100 nanometers down an ultimate 1 nanometer, which is a billionth of a meter. Just imagine, for comparison, that the thickness of a human hair is forty thousand nanometers. In fact, you could fit one million skyrmions on the head of a pin. Skyrmions can be quite small indeed!
- Skyrmionics team, University of Manchester
- Nano Engineering and Storage Technologies group, University of Manchester
- MAGicSky consortium
- Unité Mixte de Physique, CNRS, Thales, France
- PolLux beamline at the Swiss Light Source
- Laboratory for Mesoscopic Systems, Department of Materials, ETH Zurich
- Max Planck Institute for Intelligent Systems, Germany
Financial support is acknowledged from the European Union grant MAGicSky No. FET-Open-665095, the Agence Nationale de la Recherche project ANR-14-CE26-0012 ULTRASKY and the School of Computer Science, University of Manchester start-up fund.