title: Sequence of Silicon Monolayer Structures Grown on a Ru Surface: from a Herringbone Structure to Silicene.
abstract: Silicon-based two-dimensional (2D) materials are uniquely suited for integration in Si-based electronics. Silicene, an analogue of graphene, was recently fabricated on several substrates and was used to make a field-effect transistor. Here, we report that when Ru(0001) is used as a substrate, a range of distinct monolayer silicon structures forms, evolving toward silicene with increasing Si coverage. Low Si coverage produces a herringbone structure, a hitherto undiscovered 2D phase of silicon. With increasing Si coverage, herringbone elbows evolve into silicene-like honeycomb stripes under tension, resulting in a herringbone-honeycomb 2D superlattice. At even higher coverage, the honeycomb stripes widen and merge coherently to form silicene in registry with the substrate. Scanning tunneling microscopy (STM) was used to image the structures. The structural stability and electronic properties of the Si 2D structures, the interaction between the Si 2D structures and the Ru substrate, and the evolution of the distinct monolayer Si structures were elucidated by density functional theory (DFT) calculations. This work paves the way for further investigations of monolayer Si structures, the corresponding growth mechanisms, and possible functionalization by impurities.
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.|Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Li
authors.initials: L
authors.lastname: Huang
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.|Department of Physics and Astronomy and Department of Electrical Engineering and Computer Science, Vanderbilt University , Nashville, Tennessee 37235, United State.
authors.forename: Yan-Fang
authors.initials: YF
authors.lastname: Zhang
authors.affiliation: School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences , Beijing 100049, P. R. China.|Department of Physics and Astronomy and Department of Electrical Engineering and Computer Science, Vanderbilt University , Nashville, Tennessee 37235, United State.
authors.forename: Yu-Yang
authors.initials: YY
authors.lastname: Zhang
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Wenyan
authors.initials: W
authors.lastname: Xu
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Yande
authors.initials: Y
authors.lastname: Que
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: En
authors.initials: E
authors.lastname: Li
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Jin-Bo
authors.initials: JB
authors.lastname: Pan
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.|School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Ye-Liang
authors.initials: YL
authors.lastname: Wang
authors.affiliation: Institute of Chemistry, Chinese Academy of Sciences , Beijing 100190, P. R. China.
authors.forename: Yunqi
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.|School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Shi-Xuan
authors.identifier: 0000-0001-9323-1307
authors.initials: SX
authors.lastname: Du
authors.affiliation: School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences , Beijing 100049, P. R. China.|Department of Physics and Astronomy and Department of Electrical Engineering and Computer Science, Vanderbilt University , Nashville, Tennessee 37235, United State.
authors.forename: Sokrates T
authors.initials: ST
authors.lastname: Pantelides
authors.affiliation: Institute of Physics, Beijing Key Laboratory for Nanomaterials and Nanodevices, Chinese Academy of Sciences , Beijing 100190, P. R. China.|School of Physical Sciences and CAS Key Laboratory of Vacuum Physics, University of Chinese Academy of Sciences , Beijing 100049, P. R. China.
authors.forename: Hong-Jun
authors.initials: HJ
authors.lastname: Gao