We investigate the interactions between two symmetric monovacancy defects in graphene grown on Ru(0001) after silicon intercalation by combining first-principles calculations with scanning tunneling microscopy(STM). F...We investigate the interactions between two symmetric monovacancy defects in graphene grown on Ru(0001) after silicon intercalation by combining first-principles calculations with scanning tunneling microscopy(STM). First-principles calculations based on free-standing graphene show that the interaction is weak and no scattering pattern is observed when the two vacancies are located in the same sublattice of graphene, no matter how close they are, except that they are next to each other. For the two vacancies in different sublattices of graphene, the interaction strongly influences the scattering and new patterns' emerge, which are determined by the distance between two vacancies. Further experiments on silicon intercalated graphene epitaxially grown on Ru(0001) shows that the experiment results are consistent with the simulated STM images based on free-standing graphene, suggesting that a single layer of silicon is good enough to decouple the strong interaction between graphene and the Ru(0001) substrate.展开更多
基金Project supported by the National Key Research and Development Program of China(Grant Nos.2016YFA0202300 and 2018YFA0305800)the National Natural Science Foundation of China(Grant Nos.61622116,61474141,61390501,and 11604373)the Pioneer Hundred Talents Program,Chinese Academy of Sciences
文摘We investigate the interactions between two symmetric monovacancy defects in graphene grown on Ru(0001) after silicon intercalation by combining first-principles calculations with scanning tunneling microscopy(STM). First-principles calculations based on free-standing graphene show that the interaction is weak and no scattering pattern is observed when the two vacancies are located in the same sublattice of graphene, no matter how close they are, except that they are next to each other. For the two vacancies in different sublattices of graphene, the interaction strongly influences the scattering and new patterns' emerge, which are determined by the distance between two vacancies. Further experiments on silicon intercalated graphene epitaxially grown on Ru(0001) shows that the experiment results are consistent with the simulated STM images based on free-standing graphene, suggesting that a single layer of silicon is good enough to decouple the strong interaction between graphene and the Ru(0001) substrate.
