Dirac cone move and bandgap on/off switching of graphene superlattice

Tian Tian Jia, Meng Meng Zheng, Xin Yu Fan, Yan Su, Shu Juan Li, Hai Ying Liu, Gang Chen, Yoshiyuki Kawazoe

Research output: Contribution to journalArticlepeer-review

16 Citations (Scopus)

Abstract

Using the density functional theory with generalized gradient approximation, we have studied in detail the cooperative effects of degenerate perturbation and uniaxial strain on bandgap opening in graphene. The uniaxial strain could split π bands into πa and πz bands with an energy interval Es to move the Dirac cone. The inversion symmetry preserved antidot would then further split the πaz) bands into πa1z1) and πa2z2) bands with an energy interval Ed, which accounts for the bandgap opening in a kind of superlattices with Dirac cone being folded to Γ point. However, such antidot would not affect the semimetal nature of the other superlattices, showing a novel mechanism for bandstructure engineering as compared to the sublattice-equivalence breaking. For a superlattice with bandgap of ∼Ed opened at Γ point, the Es could be increased by strengthening strain to close the bandgap, suggesting a reversible switch between the high velocity properties of massless Fermions attributed to the linear dispersion relation around Dirac cone and the high on/off ratio properties associated with the sizable bandgap. Moreover, the gap width actually could be continuously tuned by controlling the strain, showing attractive application potentials.

Original languageEnglish
Article number18869
JournalScientific reports
Volume6
DOIs
Publication statusPublished - 2016 Jan 6

ASJC Scopus subject areas

  • General

Fingerprint Dive into the research topics of 'Dirac cone move and bandgap on/off switching of graphene superlattice'. Together they form a unique fingerprint.

Cite this