"Our discovery could provide a new device platform to the spintronic industry, which at present struggles with issues around instability and scalability due to the thin magnetic elements that are used," said Associate Professor Yang Hyunsoo from the NUS Department of Electrical and Computer Engineering.
Today, digital information is being generated in unprecedented amounts all over the world, and as such there is an increasing demand for low-cost, low-power, highly-stable, and highly-scalable memory and computing products. One way this is being achieved is with new spintronic materials, where digital data are stored in up or down magnetic states of tiny magnets. However, while existing spintronic memory products based on ferromagnets succeed in meeting some of these demands, they are still very costly due to scalability and stability issues.
"Ferromagnet-based memories cannot be grown beyond a few nanometres thick as their writing efficiency decays exponentially with increasing thickness. This thickness range is insufficient to ensure the stability of stored digital data against normal temperature variations," explained Dr Yu Jiawei, who was involved in this project while pursuing her doctoral studies at NUS.
To address these challenges, the team fabricated a magnetic memory device using ferrimagnets, which they discovered can be grown 10 times thicker without compromising on the overall data writing efficiency.