Produção Nacional
Ab initio quasiparticle band structure of ABA and ABC-stacked graphene trilayers
2014; American Physical Society; Volume: 89; Issue: 3 Linguagem: Inglês
10.1103/physrevb.89.035431
ISSN1550-235X
AutoresMarcos G. Menezes, Rodrigo B. Capaz, Steven G. Louie,
Tópico(s)Boron and Carbon Nanomaterials Research
ResumoWe obtain the quasiparticle band structure of ABA and ABC-stacked graphene trilayers through ab initio density-functional theory (DFT) and many-body quasiparticle calculations within the $GW$ approximation. To interpret our results, we fit the DFT and $GW$ $\ensuremath{\pi}$ bands to a low-energy tight-binding model, which is found to reproduce very well the observed features near the $K$ point. The values of the extracted hopping parameters are reported and compared with available theoretical and experimental data. For both stackings, the self-energy corrections lead to a renormalization of the Fermi velocity, an effect also observed in previous calculations on monolayer graphene. They also increase the separation between the higher-energy bands, which is proportional to the nearest-neighbor interlayer hopping parameter ${\ensuremath{\gamma}}_{1}$. Both features are brought to closer agreement with experiment through the self-energy corrections. Finally, other effects, such as trigonal warping, electron-hole asymmetry, and energy gaps, are discussed in terms of the associated parameters.
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