Claiming the potential for the device to act as a ‘universal memory’, lead researcher Dr Peter Wadley, from the University of Nottingham, said: “This work demonstrates the first electrical current control of antiferromagnets. It uses an entirely new physical phenomenon and, in doing so, demonstrates the first all antiferromagnetic memory device. This could be hugely significant, as antiferromagnets have an intriguing set of properties, including a theoretical switching speed limit approximately 1000 times faster than the best current memory technologies.”
According to the team, their development does not produce magnetic fields, meaning elements can be packed more closely, leading to higher storage density. Antiferromagnetic memory is also insensitive to magnetic fields and radiation.
Using CuMnAs, grown layer by layer in an almost complete vacuum, the team demonstrated that the alignment of the magnetic moments of certain types of antiferromagnets can be controlled with electrical pulses.
Dr Frank Freimuth of the Peter Grünberg Institute noted: “The electric current brings about a quantum mechanical torque on individual spins and allows each of them to tilt by 90°.”
Dr Wadley said: “Another foreseen advantage, which is yet to be established, is the speed by which information can be written in antiferromagnetic memories. Its physical limit is hundreds to thousands of times greater than in ferromagnets.
“The potential increase in speed of operation, robustness, energy efficiency and storage density could have a huge commercial and societal impact.”
