Dirac cone in α -graphdiyne: a first-principles study
Key Laboratory for Magnetism and Magnetic Materials of the Ministry of Education, Lanzhou University, 222 South Tianshui Road, Lanzhou 730000, China
Nanoscale Research Letters 2013, 8:469 doi:10.1186/1556-276X-8-469Published: 9 November 2013
We investigate the Dirac cone in α-graphdiyne, which is a predicted flat one-atom-thick allotrope of carbon using first-principles calculations. α-graphdiyne is derived from graphene where two acetylenic linkages (-C ≡C-) are inserted into the single bonds (-C-C-). Thus, α-graphdiyne possesses a larger lattice constant which subsequently affects its electronic properties. Band structures show that α-graphdiyne exhibits similar Dirac points and cone to graphene. Further, the tight-binding method is used to exploit the linear dispersion in the vicinity of Dirac points. Thanks to the larger lattice constant, α-graphdiyne yields a lower Fermi velocity, which might make itself an ideal material to serve the anomalous integer quantum Hall effect.