상세정보
학술지
Configuration of Ripple Domains and Their Topological Defects Formed under Local Mechanical Stress on Hexagonal Monolayer Graphene
- 저자
- 박영구, 최진식, 최택집, 이미정, Quanxi Jia, 박민우, 이훈경, 박배호
- 발행일
- 201503
- 출처
- Scientific Reports, v.5, pp.1-6
- ISSN
- 2045-2322
- 출판사
- Nature Publishing Group
- 협약과제
- 15ZE1100, ETRI 창의연구실 사업, 정성영
- 초록
- Ripples in graphene are extensively investigated because they ensure the mechanical stability of two-dimensional graphene and affect its electronic properties. They arise from spontaneous symmetry breaking and are usually manifested in the form of domains with long-range order. It is expected that topological defects accompany a material exhibiting long-range order, whose functionality depends on characteristics of domains and topological defects. However, there remains a lack of understanding regarding ripple domains and their topological defects formed on monolayer graphene. Here we explore configuration of ripple domains and their topological defects in exfoliated monolayer graphenes on SiO2 /Si substrates using transverse shear microscope. We observe three-color domains with three different ripple directions, which meet at a core. Furthermore, the closed domain is surrounded by an even number of cores connected together by domain boundaries, similar to topological vortex and anti-vortex pairs. In addition, we have found that axisymmetric three-color domains can be induced around nanoparticles underneath the graphene. This fascinating configuration of ripple domains may result from the intrinsic hexagonal symmetry of two-dimensional graphene, which is supported by theoretical simulation using molecular dynamics. Our findings are expected to play a key role in understanding of ripple physics in graphene and other two-dimensional materials.
- KSP 제안 키워드
- Electronic properties, Graphene ripples, Hexagonal monolayer, Hexagonal symmetry, Key role, Long-range order, Mechanical stability, Molecular dynamics(MD), Monolayer graphene, Si substrate, Topological defects