Graphene is extremely strong for its weight, it's electrically and thermally conductive, and it's chemically stable ... but it isn't magnetic. Now, however, a team from the University of California, Riverside has succeeded in making it so. The resulting magnetized graphene could have a wide range of applications, including use in "spintronic" computer chips.
While other groups have previously magnetized graphene, they've done so by doping it with foreign substances, and the presence of these impurities has negatively affected its electronic properties. In this case, though, the graphene was able to remain pure.
Led by professor of physics and astronomy Jing Shi, the UC Riverside team laid a sheet of regular graphene down on an atomically smooth layer of magnetic yttrium iron garnet. That material then simply magnetized the graphene as it lay against it. Yttrium iron garnet was used due to the fact that certain other magnetic materials could disrupt the graphene’s electrical transport properties.
When the sheet of graphene was removed and subsequently exposed to a magnetic field, it was shown to indeed possess magnetic qualities of its own.
"This is the first time that graphene has been made magnetic this way," said Shi. "The magnetic graphene acquires new electronic properties so that new quantum phenomena can arise. These properties can lead to new electronic devices that are more robust and multi-functional."
Those devices could include improved spintronic chips, that use the spin of electrons – which can be magnetically manipulated – to store data.
University of California, Riverside