Dirac electrons broken to pieces

Nature : The fractional quantum Hall effect (FQHE) is a fascinating form of collective electronic behavior.It arises when electrons in a strong magnetic field—applied at a right angle to the plane in which the electrons flow—act together to behave like particles with a charge that is a fraction of an electron’s charge.Its observation requires the use of two-dimensional systems virtually free of disorder. This is why, since its discovery by Daniel Tsui and Horst Störmer in 1982—for which they won the 1998 Nobel Physics prize—the effect has been studied in ultrapure semiconductor heterostructures (devices that contain thin layers of one or more semiconductors) grown in an ultrahigh vacuum.Two papers, one by Xu Du and colleagues and Kirill I. Bolotin and colleagues , show that the FQHE can also be observed in graphene —a one-atom-thick sheet of graphitic carbon, the production of which requires no more sophistication than a common adhesive tape to manually exfoliate graphite in ambient conditions Related Links Fractional quantum Hall effect and insulating phase of Dirac electrons in graphene Observation of the fractional quantum Hall effect in graphene