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Incoming links: Andre Geim
Andre Geim Created 2026-10-18 Updated 2026-11-05
Andre Geim coauthored measurements showing that electric charge carriers in graphene can behave as effectively massless quasiparticles described by the Dirac equation. The 2005 experiments found an unusual sequence of quantum Hall effect plateaus and an oscillation phase associated with Berry phase. Here the Dirac description concerns low-energy quasiparticles in a carbon lattice, rather than free electrons acquiring zero rest mass. The results connect a readily contacted material with concepts usually introduced in relativistic quantum mechanics.[ref]
A physicist researching condensed matter physics, including graphene.[ref]
Sir Andre Geim FRS by Royal Society. Independent professional identity
Portrait of Andre Geim
. Bengt Oberger, own photograph, 9 December 2018. Creative Commons Attribution-Share Alike 4.0 International., via Wikimedia Commons. Source.
Andre Geim, Konstantin Novoselov and collaborators mechanically cleaved graphite, identified thin flakes, and fabricated multi-terminal Hall bars on oxidized silicon. A substrate gate changed the carrier density; longitudinal electrical resistance and the Hall coefficient supplied different checks. The 2004 report included one-, two- and three-layer devices and described a few-layer semimetal interpretation. Layer identification and electrical control were separate experimental achievements.[ref]
Electric Field Effect in Atomically Thin Carbon Films by Konstantin Novoselov and others. pp.1–2 and Figs.1–2: preparation, thickness selection and electrical measurements
The 2005 monolayer study used an optical microscope, electron microscopy and atomic force microscopy to select monolayers. It then measured Shubnikov-de Haas oscillations as temperature, gate voltage and magnetic field varied. Their damping inferred a density-dependent cyclotron effective mass; comparison with oscillation frequency tested a linear dispersion relation. A comparison with two-layer devices also distinguished their quantum Hall effect sequences. These are complementary tests of the monolayer model, rather than consequences of finding a thin-looking flake alone.[ref]
Two-Dimensional Gas of Massless Dirac Fermions in Graphene by Konstantin Novoselov and others. pp.1–3, Figs.2–4: monolayer selection, oscillation damping and bilayer comparison
Nobel Prize in Physics in 2010 2026-10-18
Awarded in equal shares to Andre Geim and Konstantin Novoselov for pioneering experiments on the two-dimensional material graphene.[ref]
The Nobel Prize in Physics 2010 by Nobel Prize Outreach. Individual official summary: Geim and Novoselov one half each; experiments on two-dimensional graphene.