Tunable electronic properties in stanene and two dimensional silicon-carbide heterobilayer: A first principles investigation

摘要

A novel two-dimensional heterobilayer, stanene-silicon carbide (Sn/SiC) is predicted using first principles calculations. Three representational stacking configurations are considered to study the structure and electronic properties of Sn/SiC heterobilayer in detail. All the stacking patterns of the heterobilayer manifest a wide band gap of ∼160meV at the K point with the Dirac cone well preserved, exhibiting the largest energy band gap among all stanene-based two dimensional heterostructures. Moreover, the energy gap can be efficiently varied through changing the interlayer distance between stanene and SiC layer as well as applying biaxial strain. Our computed small effective mass (∼0.0145mo) and the characteristic of nearly linear band dispersion relation of the heterobilayer also suggest high mobility of the carriers. The space charge distribution of the valence and conduction bands and the density of states (DOS) of the heterostructure unravel that SiC monolayer retains the various excellent electrical properties of stanene in a great extent and allows the carriers to move through the stanene layer only. This implies the potentiality of 2D SiC as a good substrate for stanene to adopt the heterobilayer. Our results reveal that Sn/SiC heterobilayer would be a promising platform for future Sn-based high speed nanoelectronic and spintronic devices.