First-principles investigations on twist-shaped device based on silicon carbide nanoribbons
In this paper,the structure is based on zigzag silicon carbide nanoribbons(ZSiCNRs),with the middle section translating upward spatially and then flipping 180°.Thus,a twist-shaped tri-probe heterojunction device would be formed,which reserves the carbon edge channel.According to density functional theory(DFT)and non-equilibrium Green's function(NEGF)calculation method,the elec-tron transport properties of the tri-probe device are investigated.The results indicate that one kind of spin electron can transit from one electrode to the other via the single side channel of the heterojunc-tion in both ferromagnetic(FM)and antiferromagnetic(AFM)states,achieving 100％spin-polarized electron transport.When the gate voltage is applied to the central region,the current decreases with the increase of the gate voltage.When the gate voltage is greater than 0.5 V,the electron transport channel is completely blocked and both spin electrons cannot pass through the tri-probe device,indica-ting that the electron transport capacity of the device can be regulated by the gate voltage.Further-more,if the device is deformed by external force,the electron transport capacity is almost unchanged as long as the shape variable is less than 6.7％.The findings provide a strong theoretical basis for the design of pure spin current devices based on silicon carbide nanoribbons.
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