Impurity scattering and size quantization effects in a single graphene nanoflake

Review

关键词: EPITAXIAL GRAPHENE;    ELECTRONIC-PROPERTIES;    NANORIBBONS;    FABRICATION;    TRANSPORT;    AG(111);    STATE;    FILMS;   

DOI  :  10.1103/PhysRevB.95.075429

来源: SCIE

【 摘 要 】

By using Fourier-transform scanning tunneling spectroscopy we measure the interference patterns produced by the impurity scattering of confined Dirac quasiparticles in epitaxial graphene nanoflakes. Upon comparison of the experimental results with tight-binding calculations of realistic model flakes, we show that the characteristic features observed in the Fourier-transformed local density of states are related to scattering between different transverse modes (subbands) of a graphene nanoflake and allow direct insight into the gapped electronic spectrum of graphene. We also observe a strong reduction of quasiparticle lifetime which is attributed to the interaction with the underlying substrate. In addition, we show that the distribution of the on-site energies at flower defects leads to an effectively broken pseudospin selection rule, where intravalley backscattering is allowed.

【 授权许可】

Free