Researchers from Kaiserslautern and Mainz have uncovered a novel approach in the field of magnetic memories, highlighting the synergy between ferromagnetic and antiferromagnetic materials. In a study published in Physical Review Letters, they discuss how a thin antiferromagnet/ferromagnet bilayer can combine the strengths of both classes of materials.
Ferromagnets, with their net magnetization, are easily excited and operate in the gigahertz range, making them useful for various applications. On the other hand, antiferromagnets, although lacking external magnetic properties, exhibit rapid dynamics in the terahertz range once excited, making them appealing for communication technologies and magnetic memories.
The researchers crafted a hybrid material composed of these layers, showcasing a unique coupling at the antiferromagnetic-ferromagnetic interface. This coupling is so strong that the antiferromagnetic spins align themselves based on the magnetization in the ferromagnet. This distinctive property allows for the transfer of magnetic excitation from the ferromagnet to the antiferromagnet, resulting in a higher frequency than that of a pure ferromagnet.
Such findings hold promise for future applications, particularly in emerging mobile technologies requiring higher frequencies. Additionally, memory technologies like Magnetic Random-Access Memory and microwave generation through spin-torque oscillators could benefit from this innovative approach, ultimately enhancing performance.