Spin transport in silicene and germanene

Abstract

In this article, we have investigated spin polarized electronic transport in two dimensional sheet materials of silicon and germanium, such as, monolayer silicene and germanene, using semi-classical Monte-Carlo approach. Monte-Carlo simulations are used to model spin transport along with spin density matrix calculations in the devices. Dephasing of the spin vectors in silicene and germanene are due to primarily D'yakonov–Perel (DP) and Elliott–Yafet (EY) relaxation mechanisms. But, as silicene and germanene has high carrier mobility the latter one is not the dominant relaxation mechanism. In this work, we studied spin polarized transport along the length of the planar monolayer silicene, buckled monolayer silicene and germanene monolayer structure and the spin dephasing length is estimated to be in the range of 0.5 μm for silicene and 1.5 μm for germanene. We also investigated the ensemble averaged spin vector variation along the length of the planar and buckled monolayer silicene and germanene with varying temperature. Finally, we studied the effect of variation of vertical electric field (Ez) on spin dephasing length in silicene buckled monolayer structure. Silicene and germanene show significant potential for future nanoelectronics devices.