Graphene is a wonder material. It can act as a superconductor, generate a super-rare form of magnetism, and unlock entirely new quantum states.
- Now graphene has added another feature; it can record levels of giant magnetoresistance (GMR) without a need to push the temperature down towards absolute zero.
Key points
- In this latest experiment, researchers from the UK led by Nobel laureate Andre Geim, exposed high-quality graphene to magnetic fields at room temperature and measured its response.
- High magnetoresistance – a material’s ability to change its electrical resistance in response to a magnetic field.
- Say a conductor is sandwiched between two ferromagnetic materials (commonly, metals attracted to magnets, like iron). When the materials are magnetised in the same direction, the electrical resistance in the conductor is low. When the directions are opposite each other, the resistance increases. This is GMR.
- GMR is relatively rare, yet materials that can shift their properties in this fashion are useful in computers, cars, and medical equipment. The most interesting graphene behavior, and indeed the highest levels of magnetoresistance, are usually observed at ultra-low temperatures.
- GMR is used in harddisk drives and magnetoresistive RAM in computers, biosensors, automotive sensors, microelectromechanical systems, and medical imagers.
About Graphene
- Graphene is a one-atom-thick layer of carbon atoms arranged in a hexagonal lattice.
- It is the building-block of Graphite (which is used, among others things, in pencil tips), but graphene is a remarkable substance on its own – with a multitude of astonishing properties which repeatedly earn it the title a wonder material.
- Graphene is the thinnest material known to man at one atom thick, and also incredibly strong – about 200 times stronger than steel.
- Graphene is an excellent conductor of heat and electricity and has interesting light absorption abilities.
