Researchers at MIT have developed a new way of controlling the motion of magnetic domains—the key technology in magnetic memory systems, such as a computer's hard disk. The new approach requires little power to write and no power to maintain the stored information, and could lead to a new generation of extremely low-power data storage .
The new approach controls magnetism by applying a voltage, rather than a magnetic field. It could lead to magnetic storage devices in which data is written on microscopic nanowires or tracks, with magnetic "bits" of data hurtling along them like cars on a racetrack.
The new findings are described in a paper published this week in the journal Nature Nanotechnology, written by assistant professor of materials science and engineering Geoffrey Beach and graduate students Uwe Bauer and Satoru Emori.
"For hundreds of years, if you had a magnetic material and you wanted to change the direction in which the material was magnetized, you needed another magnet," Beach explains. His team's work represents an entirely new way to switch magnetic states using just a change in voltage, with no magnetic field—a much lower-power process. What's more, once the magnetic state is switched, it holds that change, providing stable data storage that requires no power except during reading and writing.
The researchers show that this effect can be used to enable new concepts such as "racetrack memory," with magnetic bits speeding along a magnetic track. While there have been laboratory demonstrations of such devices, none have come close to viability for data storage: The missing piece has been a means to precisely control the position and to electrically select individual magnetic bits racing along the magnetic track.
"Magnetic fields are very hard to localize," Beach says: If you're trying to create tiny magnetic bits on a nanowire or track, the magnetic fields from the electromagnets used to read and write data tend to spread out, making it difficult to prevent interaction with adjacent strips, especially as devices get smaller and smaller.
No comments:
Post a Comment