Discovery of graphene

[12] Semenoff emphasized the occurrence in a magnetic field of an electronic Landau level precisely at the Dirac point.

An early, detailed study on few-layer graphite dates to 1962 when Boehm reported producing monolayer flakes of reduced graphene oxide.

Single layers of graphite were observed by TEM within bulk materials, in particular inside soot obtained by chemical exfoliation.

[3][4] Initial attempts to make atomically thin graphitic films employed exfoliation techniques similar to the drawing method.

Earlier researchers tried to isolate graphene starting with intercalated compounds, producing very thin graphitic fragments (possibly monolayers).

[20] Neither of the earlier observations was sufficient to launch the "graphene gold rush" that awaited macroscopic samples of extracted atomic planes.

The silicon beneath the SiO2 could be used as a "back gate" electrode to vary the charge density in the graphene over a wide range.

The key to success was high-throughput visual recognition of graphene on a properly chosen substrate that provides a small but noticeable optical contrast.

Geim and Novoselov received awards for their pioneering research on graphene, notably the 2010 Nobel Prize in Physics.