• 文献标题:   Observation of high-order moire effect and multiple Dirac fermions replicas in graphene-SiC heterostructures
  • 文献类型:   Article
  • 作  者:   WU CL, WAN Q, PENG C, MO SK, LI RZ, ZHAO KM, GUO YP, HUO D, ZHANG CD, XU N
  • 作者关键词:  
  • 出版物名称:   PHYSICAL REVIEW B
  • ISSN:   2469-9950 EI 2469-9969
  • 通讯作者地址:  
  • 被引频次:   2
  • DOI:   10.1103/PhysRevB.104.235130
  • 出版年:   2021

▎ 摘  要

Moire potential has become a powerful tool to modulate electronic structures and realize quantum phases. Authors of previous studies mainly focused on the first-order moire effect in systems with small lattice mismatches and rotation angles. Here, we report evidence of a high-order moire effect and multiple Dirac cone replicas by performing angle-resolved photoemission spectroscopy on a graphene-SiC heterostructure. Despite that the first-order moire effect is weak due to large lattice mismatch and rotation angle, a high-order moire effect with a 1.9 nm periodicity in real-space is experimentally observed. Different from previously studied first-order moire systems, in which only replicas with momentum transfer by the primitive reciprocal lattice vectors were observed, Dirac cone replicas with momentum transfer by second- and third-order reciprocal lattice vectors are experimentally identified. Our results not only demonstrate the high-order moire effect in a graphene-SiC heterostructure but also provide opportunities to engineer moire systems without the limitation of small lattice constant mismatches.