18th century paint Cobalt Green will allow spintronics to work at room temperature To test the antique pigment the researchers processed zinc oxide, a simple semiconductor material, so that some of the zinc ions were replaced with ions of magnetic cobalt. The process is known as “doping”. The cobalt ions were then aligned by exposing the semiconductor to a zinc metal vapour. The alignment causes the material to become magnetic. The magnetism continued when the material was warmed to room temperature and when the exposure to the zinc metal vapour was stopped.
The research is still in its early stages. To be of use to chip-makers the technique must be shown to work and integrate with silicon semiconductors.