Chameleon magnets that switch 'on - off' could revolutionise computing

A study by Japanese scientists has reported the possibility to turn a material's magnetism on and off at room temperature - an advancement that could revolutionise computing, forming the basis of high-capacity and low-energy memory, data storage and data transfer devices.

A team led by researchers at Tohoku University added cobalt to titanium dioxide, a nonmagnetic semiconductor, to create a new material that, like a chameleon, can transform from a paramagnet (a nonmagnetic material) to a ferromagnet (a magnetic material) at room temperature.

To achieve change, the researchers applied an electric voltage to the material, exposing the material to extra electrons. As Buffalo researcher Igor Zutic, a theoretical physicist and fellow UB physicist John Cerne explain in their commentary, these additional electrons -- called "carriers" -- are mobile and convey information between fixed cobalt ions that causes the spins of the cobalt electrons to align in one direction.

In their Science commentary, Zutic and Cerne write that chameleon magnets could "help us make more versatile transistors and bring us closer to the seamless integration of memory and logic by providing smart hardware that can be dynamically reprogrammed for optimal performance of a specific task."

"Large applied magnetic fields can enforce the spin alignment in semiconductor transistors," they said.

"With chameleon magnets, such alignment would be tunable and would require no magnetic field and could revolutionize the role ferromagnets play in technology,” they added.

The study was recently published in the journal Science.