The Effect Of Disorder On Transport Properties Of Silicene In The Presence Of An External Electric Field

In recent years,because of many special transport properties,the research in silicene has been an active field in 2D semiconductor materials.In this paper,by using tight-binding approximation theory and non-equilibrium Green's function method,the effect of external vertical electric field and non-magnetic impurities on monolayer silicene nanoribbon is calculated and analyzed theoretically.We implement the disorder effect of silicene by adding a random disorder potential at each lattice point in the silicene nanoribbon.Considering the influence of the Rashba spin-orbit coupling and intrinsic spin-orbit coupling on silicene,by using non-equilibrium Green's function method and muti-channel transmission theory,we studied the effect of vertical electric field and non-magnetic impurities on transport properties of silicene.The results show that: due to the vertical electric field,the degeneracy of energy levels is removed.With the increase of the electric field strength,the band gap width of the silicene is reduced,resulting in narrowing of the perfect polarized valley plateau width.Irrespective of the influence of non-magnetic impurities on the system,K valley,K' valley and the total conductance of the system exhibit a step-like structure,and the electron transport is performed in their respective valleys;When considering the non-magnetic impurities,due to non-magnetic impurities,the localization of the charge enhances.Scattering of carriers by impurities destroys K valley and K' valley conduction platform structure,but the edge states are not affected by impurities.The transmission of edge states is still in the respective valley,the perfect valley polarization platform structure was not destroyed,showing the robustness of the edge transport of silicene.