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.

Recently, two-dimensional silicon carbide (2D-SiC) has attracted considerable interest due to its exotic electronic and optical properties. Here, we explore the thermal properties of 2D-SiC using reverse non-equilibrium molecular dynamics simulation. At room temperature, a thermal conductivity of ∼313 W mK −1 is obtained for 2D-SiC which is one order higher than that of silicene. Above room temperature, the thermal conductivity deviates the normal 1/T law and shows an anomalous slowly decreasing behavior. To elucidate the variation of thermal conductivity, the phonon modes at different length and temperature are quantified using Fourier transform of the velocity auto-correlation of atoms. The calculated phonon density of states at high temperature shows a shrinking and softening of the peaks, which induces the anomaly in the thermal conductivity. On the other hand, quantum corrections are applied to avoid the freezing effects of phonon modes on the thermal conductivity at low temperature. In addition, the effect of potential on the thermal conductivity calculation is also studied by employing original and optimized Tersoff potentials. These findings provide a means for better understating as well as designing the efficient thermal management of 2D-SiC based electronics and optoelectronics in near future.

We explored the effect of vacancies (bi vacancy, point vacancy, and mixed vacancy) on the phonon thermal transport behavior of 2D-SiC using RNEMD simulations.

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