IBM: Racetrack memory instead of MRAM or hard disks
In racetrack memory, magnetic domain walls – boundaries between magnetic regions or "domains" in a magnetic material – are made to speed along nanowires made of magnetic material as if they were on a racetrack. In the process, the movable domain walls can be used as a type of magnetic shift register for storing data bits.
Several teams of scientists are working on getting racetrack memory ready for mass products. IBM now claims to have come a step closer to this goal: Dr. Stuart Parkin of IBM's Almaden research lab in California, who used to develop MRAM technology, has now published an article about the subject in Science magazine. His team managed to influence the walls between magnetic domains in permanently magnetic nanowires by applying spin polarised currents, a technique referred to as Spin Torque Transfer or STT. According to the report, the nanowires can also be arranged both perpendicularly and horizontally on the surface of silicon semiconductor components. This three-dimensional racetrack memory promises extremely high storage densities. Reading and writing the data is also said to be very fast, because every nanowire has its own read/write unit.
IBM explains the new technology both in a press release and in a YouTube video. Unfortunately, there is no mention of the MRAM co-operation with TDK which was announced last year. The Japanese group is a major producer and innovator in the field of magnetic materials. It remains unclear whether TDK is also co-operating with IBM in the field of racetrack memory.