Negative-Differential-Resistance Devices Achieved by Band-Structure Engineering in Silicene under Periodic Potentials

In terms of band-gap engineering for devices, despite silicene's great promise, it has received considerably less attention than its carbon cousin graphene. Taking advantage of its tunable band gap, the authors use an effective Hamiltonian formalism to examine the formation of silicene superlattices. They theoretically consider engineering of the local band structure of silicene through application of an out-of-plane electric field, together with control over the spin and valley degrees of freedom, and finally show how to optimize negative differential resistance. This design principle could be extended to stacks of other two-dimensional materials as well.