Stretching an atom-thick strip of carbon could mimic the effects of a magnetic field, changing the behaviour of electrons so that the effect is 100 times stronger than that from normal magnets.
Teng Li at the University of Maryland in College Park and his colleagues calculated how to engineer the large pseudomagnetic fields that are produced when graphene is pulled from two ends. This strains bonds between carbon atoms, causing their electrons to move in a way that is similar to what happens in a magnetic field. The team found that a small tug (of up to 15% stretch) on certain shapes of graphene strip could produce a strong, nearly uniform field.
The designer shapes could help researchers to study the properties of graphene under extreme conditions — such as large magnetic fields — that are usually unattainable, the authors say.