• 文献标题:   Inducing a topological transition in graphene nanoribbon superlattices by external strain
  • 文献类型:   Article
  • 作  者:   FLORES E, MELLA JD, APARICIO E, GONZALEZ RI, PARRA C, BRINGA EM, MUNOZ F
  • 作者关键词:  
  • 出版物名称:   PHYSICAL CHEMISTRY CHEMICAL PHYSICS
  • ISSN:   1463-9076 EI 1463-9084
  • 通讯作者地址:  
  • 被引频次:   1
  • DOI:   10.1039/d2cp00038e EA FEB 2022
  • 出版年:   2022

▎ 摘  要

Armchair graphene nanoribbons, when forming a superlattice, can be classified into different topological phases, with or without edge states. By means of tight-binding and classical molecular dynamics (MD) simulations, we studied the electronic and mechanical properties of some of these superlattices. MD shows that fracture in modulated superlattices is brittle, as for unmodulated ribbons, and occurs at the thinner regions, with staggered superlattices achieving a larger fracture strain than inline superlattices. We found a general mechanism to induce a topological transition with strain, related to the electronic properties of each segment of the superlattice, and by studying the sublattice polarization we were able to characterize the transition and the response of these states to the strain. For the cases studied in detail here, the topological transition occurred at similar to 3-5% strain, well below the fracture strain. The topological states of the superlattice - if present - are robust to strain even close to fracture. The topological transition was characterized by means of the sublattice polarization of the states.