title: Dirac cone move and bandgap on/off switching of graphene superlattice.
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 πa (πz) bands into πa1 (πz1) and πa2 (πz2) 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.
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Tian-Tian
authors.initials: TT
authors.lastname: Jia
authors.affiliation: Shandong Provincial Key Laboratory of Laser Polarization and Information Technology and Department of Physics, Qufu Normal University, Qufu, Shandong 273165, P. R. China.
authors.forename: Meng-Meng
authors.initials: MM
authors.lastname: Zheng
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Xin-Yu
authors.initials: XY
authors.lastname: Fan
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Yan
authors.initials: Y
authors.lastname: Su
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Shu-Juan
authors.initials: SJ
authors.lastname: Li
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Hai-Ying
authors.initials: HY
authors.lastname: Liu
authors.affiliation: Laboratory of Advanced Materials Physics and Nanodevices, School of Physics and Technology, University of Jinan, Jinan, Shandong 250022, P. R. China.
authors.forename: Gang
authors.initials: G
authors.lastname: Chen
authors.affiliation: New Industry Creation Hatchery Center, Tohoku University, Sendai, Miyagi 980-8577, Japan.|Kutateladze Institute of Thermophysics, Siberian Branch of Russian Academy of Sciences, Novosibirsk 630090, Russia.
authors.forename: Yoshiyuki
authors.initials: Y
authors.lastname: Kawazoe