Symmetry-dependent transport properties and magnetoresistance in zigzag silicene nanoribbons

First principles calculations are performed to study the transport properties of zigzag silicene nanoribbons (ZSiNRs). ZSiNRs show symmetry-dependent transport properties similar to those of zigzag graphene nanoribbons, although the sigma mirror plane is absent. Even-N and odd-N ZSiNRs have very different current-voltage relationships, which can be attributed to the different parity of their pi and pi* bands under c(2) symmetry operation with respect to the center axis. Moreover, magnetoresistance effect is observed in even-N ZSiNRs, and the order can reach 1 000 000%. On the basis of these interesting transport properties, ZSiNR-based logic devices, such as NOT, AND, and OR gates, are proposed. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4726276]