Researchers have unveiled the first definitive evidence of a novel form of magnetism known as altermagnetism, a discovery that may significantly impact the design of high-speed magnetic memory devices. This breakthrough was reported on December 11, 2023, in the journal Nature.
Oliver Amin, a postdoctoral researcher at the University of Nottingham, explained that traditional magnetism has two established types: ferromagnetism, where magnetic moments align in the same direction, and antiferromagnetism, where they point in opposite directions. Altermagnetism, theorized in 2022, combines characteristics of both, with adjacent magnetic moments twisted relative to each other.
This unique structure allows altermagnets to exhibit properties advantageous for information storage. They maintain the speed and resilience of antiferromagnets while incorporating time reversal symmetry breaking, a property that enhances their performance in storing and transmitting data.
The research team, led by Professor Peter Wadley, utilized photoemission electron microscopy to map the magnetic domains within manganese telluride, a material previously classified as antiferromagnetic. Their findings revealed that manipulating these magnetic structures could lead to the creation of practical altermagnetic devices.
Amin noted the potential of these devices to form vortex textures, which are increasingly recognized in spintronics as promising carriers of information. This innovative approach could pave the way for next-generation memory devices characterized by faster operational speeds and greater reliability.
Moreover, the implications of altermagnetism extend to the field of superconductivity, addressing longstanding gaps in the understanding of magnetic materials. Co-author Alfred Dal Din remarked that this discovery could bridge the divide between magnetism and superconductivity, enhancing the development of advanced materials.