Quantum Hall effect in fractal graphene: growth and properties of graphlocons

Highly dendritic graphene crystals up to 0.25 mm in diameter are synthesized by low pressure chemical vapor deposition inside a copper enclosure. With their six-fold symmetry and fractal-like shape, the crystals resemble snowflakes. The evolution of the dendritic growth features is investigated for different growth conditions, and surface diffusion is found to be the growth-limiting step responsible for the formation of dendrites. The electronic properties of the dendritic crystals are examined down to sub-Kelvin temperatures, showing a mobility of up to 6300 cm(2) V(-1) s(-1) and quantum Hall oscillations are observed above 4 T. These results demonstrate the high quality of the transport properties despite their rough dendritic edges.