The theoretically predicted phenomenon of altermagnetism was confirmed for the first time in a scientific experiment. An international team of scientists has observed a magnetic vortex in a material that has never exhibited magnetic properties. There may be hundreds of such materials, and this is an opportunity to compress the magnetic record of data a thousandfold and make a new breakthrough in computing.
Image source: Oliver Amin/University of Nottingham
Altermagnets combine – in a single material – the beneficial properties of ferromagnets and antiferromagnets. They could potentially lead to a thousandfold increase in the speed of microelectronic components and digital memory, while being more reliable and energy efficient. This is the third class of magnetism, which until this year existed only in models.
Senior Research Scientist Oliver Amin, who led the experiment and is a co-author of the study, said: “Our experimental work has provided a link between theoretical concepts and real-life implementation, which we hope will pave the way for the development of alternative magnetic materials for practical applications. “
The magnetic properties of a material depend on the spin orientation of its electrons. In ferromagnetic materials such as iron, which have a strong response to magnetic fields, the spins of all electrons are aligned in the same direction. In an antiferromagnet, another type of magnetism, the spins of neighboring electrons are in opposite directions and therefore cancel each other out, so the material as a whole does not respond to an external field. In the case of a new type of magnetism, the spins of electrons at neighboring positions are also multidirectional, but these directions constantly and symmetrically rotate.
The new pilot study was carried out at the international MAX IV facility in Sweden. This is an electron accelerator or synchrotron that generates X-rays. X-rays are directed at a magnetic material and the electrons emitted from the surface of the sample are detected using a special microscope. This makes it possible to image magnetism in a material with down to nanoscale resolution. In a sample of manganese telluride—on its surface—scientists discovered circulating magnetic vortices that fit theoretical predictions for altermagnetism.
Manganese telluride is probably not suitable for industrial applications of the phenomenon, although another non-magnetic semiconductor, chromium antimonide, may well be. Physicists predict that more than 100 compounds will exhibit non-magnetic behavior. Over the past year, about 200 papers on altermagnetism have been published, which indicates the interest and need for new and more dense data recording technology. With such activity of scientists, it cannot be ruled out that in 10 years altermagnetism will declare itself as a commercial product. What if?