| Autor: |
Polley CM; MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden.; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Fedderwitz H; MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden., Balasubramanian T; MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden., Zakharov AA; MAX IV Laboratory, Lund University, Fotongatan 2, 22484 Lund, Sweden., Yakimova R; Department of Physics, Chemistry and Biology (IFM), Linköping University, Linköping, 581 83 Sweden., Bäcke O; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Ekman J; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Dash SP; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Kubatkin S; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden., Lara-Avila S; Department of Microtechnology and Nanoscience, Chalmers University of Technology, 412 96, Gothenburg, Sweden.; National Physical Laboratory, Hampton Road, Teddington TW11 0LW, United Kingdom. |
| Abstrakt: |
The long theorized two-dimensional allotrope of SiC has remained elusive amid the exploration of graphenelike honeycomb structured monolayers. It is anticipated to possess a large direct band gap (2.5 eV), ambient stability, and chemical versatility. While sp^{2} bonding between silicon and carbon is energetically favorable, only disordered nanoflakes have been reported to date. Here we demonstrate large-area, bottom-up synthesis of monocrystalline, epitaxial monolayer honeycomb SiC atop ultrathin transition metal carbide films on SiC substrates. We find the 2D phase of SiC to be almost planar and stable at high temperatures, up to 1200 °C in vacuum. Interactions between the 2D-SiC and the transition metal carbide surface result in a Dirac-like feature in the electronic band structure, which in the case of a TaC substrate is strongly spin-split. Our findings represent the first step towards routine and tailored synthesis of 2D-SiC monolayers, and this novel heteroepitaxial system may find diverse applications ranging from photovoltaics to topological superconductivity. |
