Vibrational properties of epitaxial silicene layers on (111) Ag

• Published in: Applied surface science 2014-02, Vol.291, p.113-117
• Main Authors: Scalise, E., Cinquanta, E., Houssa, M., van den Broek, B., Chiappe, D., Grazianetti, C., Pourtois, G., Ealet, B., Molle, A., Fanciulli, M., Afanas’ev, V.V., Stesmans, A.
• Format: Article
• Language: English
• Subjects: 2D-silicon; Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; DFT; Exact sciences and technology; Physics; Raman; Silicene
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2013.08.113

•We calculated the electronic and vibrational properties of three different reconstructions of silicene on Ag(111).•The silicon structures modeled reproduce three 2D epitaxial silicon layers experimentally observed on 111 Ag, namely the (4×4), (√13×√13) and (2√3×2√3) phase.•Few peaks in the experimental Raman spectrum are identified and attributed to the silicene layers.•The trend of the intensity and frequency of the silicene Raman peaks is linked to the semimetallic or semiconductive behavior of the layers.•The band structures of the three silicene layers are calculated and confirm the indications of the Raman spectrum The electronic and vibrational properties of three different reconstructions of silicene on Ag(111) are calculated and compared to experimental results. The 2D epitaxial silicon layers, namely the (4×4), (√13×√13) and (2√3×2√3) phases, exhibit different electronic and vibrational properties. Few peaks in the experimental Raman spectrum are identified and attributed to the vibrational modes of the silicene layers. The position and behavior of the Raman peaks with respect to the excitation energy are shown to be a fundamental tool to investigate and discern different phases of silicene on Ag(111).