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Delocalized Surface State in Epitaxial Si(111) Film with Spontaneous √3 × √3 Superstructure.

ABSTRACT: The "multilayer silicene" films were grown on Ag(111), with increasing thickness above 30 monolayers (ML). Scanning tunneling microscopy (STM) observations suggest that the "multilayer silicene" is indeed a bulk-like Si(111) film with a (√3 × √3)R30° honeycomb superstructure on surface. The possibility for formation of Si(111)(√3 × √3)R30°-Ag reconstruction on the surface can be distinctively ruled out by peeling off the surface layer with the STM tip. On this surface, delocalized surface state as well as linear energy-momentum dispersion was observed from quasiparticle interference patterns. Our results indicate that a bulklike silicon film with diamondlike structure can also host delocalized surface state, which is even more attractive for potential applications, such as new generation of nanodevices based on Si.

SUBMITTER: Chen J

PROVIDER: S-EPMC4551997 | biostudies-literature | 2015 Aug

REPOSITORIES: biostudies-literature

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Delocalized Surface State in Epitaxial Si(111) Film with Spontaneous √3 × √3 Superstructure.

Chen Jian J Du Yi Y Li Zhi Z Li Wenbin W Feng Baojie B Qiu Jinlan J Cheng Peng P Xue Dou Shi S Chen Lan L Wu Kehui K

Scientific reports 20150828

The "multilayer silicene" films were grown on Ag(111), with increasing thickness above 30 monolayers (ML). Scanning tunneling microscopy (STM) observations suggest that the "multilayer silicene" is indeed a bulk-like Si(111) film with a (√3 × √3)R30° honeycomb superstructure on surface. The possibility for formation of Si(111)(√3 × √3)R30°-Ag reconstruction on the surface can be distinctively ruled out by peeling off the surface layer with the STM tip. On this surface, delocalized surface state ...[more]

PMID: 26316281

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