Dirac Fermion Cloning, Moire Flat Bands, and Magic Lattice Constants in Epitaxial Monolayer Graphene

Lu, Qiangsheng1; Le, Congcong2; Zhang, Xiaoqian1,3; Cook, Jacob1; He, Xiaoqing4,5; Zarenia, Mohammad1; Vaninger, Mitchel1; Miceli, Paul F.1; Singh, David J.1; Liu, Chang3; Qin, Hailang3; Chiang, Tai-Chang6,7; Chiu, Ching-Kai2; Vignale, Giovanni1; Bian, Guang1

2022-05-01

10.1002/adma.202200625

ADVANCED MATERIALS   影响因子和分区

0935-9648

1521-4095

Tuning interactions between Dirac states in graphene has attracted enormous interest because it can modify the electronic spectrum of the 2D material, enhance electron correlations, and give rise to novel condensed-matter phases such as superconductors, Mott insulators, Wigner crystals, and quantum anomalous Hall insulators. Previous works predominantly focus on the flat band dispersion of coupled Dirac states from different twisted graphene layers. In this work, a new route to realizing flat band physics in monolayer graphene under a periodic modulation from substrates is proposed. Graphene/SiC heterostructure is taken as a prototypical example and it is demonstrated experimentally that the substrate modulation leads to Dirac fermion cloning and, consequently, the proximity of the two Dirac cones of monolayer graphene in momentum space. Theoretical modeling captures the cloning mechanism of the Dirac states and indicates that moire flat bands can emerge at certain magic lattice constants of the substrate, specifically when the period of modulation becomes nearly commensurate with the (3 x 3)R30o\[(\sqrt 3 \; \times \;\sqrt 3 )R{30<^>o}\] supercell of graphene. The results show that epitaxial single monolayer graphene on suitable substrates is a promising platform for exploring exotic many-body quantum phases arising from interactions between Dirac electrons.

Dirac fermions epitaxial monolayers flat bands graphene moire patterns

SCI ; EI

英语

NI论文

其他

US National Science Foundation[NSF DMR-1809160] ; U.S. Department of Energy (DOE), Office of Science, Office of Basic Energy Sciences, Division of Materials Science and Engineering[DE-FG02-07ER46383] ; US Department of Energy (Office of Science)[DE-FG02-05ER46203] ; U.S. Department of Energy, Basic Energy Sciences[DE-SC0019114]

Chemistry ; Science & Technology - Other Topics ; Materials Science ; Physics

Chemistry, Multidisciplinary ; Chemistry, Physical ; Nanoscience & Nanotechnology ; Materials Science, Multidisciplinary ; Physics, Applied ; Physics, Condensed Matter

WOS:000799025200001

WILEY-V C H VERLAG GMBH

20222112149013

Clone cells ; Cloning ; High energy physics ; Lattice constants ; Lattice theory ; Modulation ; Moire fringes ; Monolayers ; Quantum theory ; Substrates

Biological Materials and Tissue Engineering:461.2 ; Genetic Engineering:461.8.1 ; Light/Optics:741.1 ; Nanotechnology:761 ; Chemical Products Generally:804 ; Mathematical Statistics:922.2 ; Quantum Theory; Quantum Mechanics:931.4 ; High Energy Physics:932.1 ; Crystal Lattice:933.1.1

MATERIALS SCIENCE

Web of Science

1.Univ Missouri, Dept Phys & Astron, Columbia, MO 65211 USA
2.RIKEN, Interdisciplinary Theoret & Math Sci iTHEMS, Wako, Saitama 3510198, Japan
3.Southern Univ Sci & Technol, Dept Phys, Shenzhen 518055, Peoples R China
4.Univ Missouri, Electron Microscopy Core Facil, Columbia, MO 65211 USA
5.Univ Missouri, Dept Mech & Aerosp Engn, Columbia, MO 65211 USA
6.Univ Illinois, Dept Phys, 1110 West Green St, Urbana, IL 61801 USA
7.Univ Illinois, Frederick Seitz Mat Res Lab, 104 South Goodwin Ave, Urbana, IL 61801 USA

Lu, Qiangsheng,Le, Congcong,Zhang, Xiaoqian,et al. Dirac Fermion Cloning, Moire Flat Bands, and Magic Lattice Constants in Epitaxial Monolayer Graphene[J]. ADVANCED MATERIALS,2022,34.

Lu, Qiangsheng.,Le, Congcong.,Zhang, Xiaoqian.,Cook, Jacob.,He, Xiaoqing.,...&Bian, Guang.(2022).Dirac Fermion Cloning, Moire Flat Bands, and Magic Lattice Constants in Epitaxial Monolayer Graphene.ADVANCED MATERIALS,34.

Lu, Qiangsheng,et al."Dirac Fermion Cloning, Moire Flat Bands, and Magic Lattice Constants in Epitaxial Monolayer Graphene".ADVANCED MATERIALS 34(2022).