Electronic structure and the minimum conductance of a graphene layer on SiO2 from density-functional methods.

M. W. C. Dharma-wardana

doi:10.1088/0953-8984/19/38/386228

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Electronic structure and the minimum conductance of a graphene layer on SiO2 from density-functional methods.

M. W. C. Dharma-wardana

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Abstract

The effect of the SiO$_2$ substrate on a graphene film is investigated using realistic but computationally convenient energy-optimized models of the substrate supporting a layer of graphene. The electronic bands are calculated using density-functional methods for several model substrates. This provides an estimate of the substrate-charge effects on the behaviour of the bands near $E_F$, as well as a variation of the equilibrium distance of the graphene sheet. A model of a wavy graphene layer is examined as a possible candidate for understanding the nature of the minimally conducting states in graphene.

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M. W. C. Dharma-wardana. 2007-04-01. Electronic structure and the minimum conductance of a graphene layer on SiO2 from density-functional methods.. https://doi.org/10.1088/0953-8984%2F19%2F38%2F386228

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