Silicene Nanoribbon Based Spin-Field Effect Transistor With Spin Filtering and Spin Seebeck Effects

The present work reports the application of density functional theory (DFT) and non-equilibrium Green's function (NEGF) formalism based framework to investigate the voltage-dependent spin transport properties for a Z-shaped silicene nanoribbon (SiNR) based spin-field effect transistor (spin-FET). The structural and magnetic properties of transition metal passivated zigzag-SiNR with symmetric and asymmetric hydrogenation at other ends have been analyzed to identify the suitability of these materials as a potential source and drain electrodes for the proposed spin-FET model. The analysis reveals that the device displays an excellent spin filtering effect and oscillatory transfer characteristics in the parallel configuration (PC) mode. Also, a high drive current and I$ _{ON}$/I$ _{OFF}$ ratio and both positive and negative transconductance are achieved. Additionally, the device generates a highly spin-polarized thermal current with the spin Seebeck effect and high spin filtration efficiency under the influence of temperature gradient. These findings defend that the proposed device model can be treated as multifunctional spintronic and spin caloritronic devices.

I. Introduction

The present electronics industry is powered by the constant miniaturization of conventional metal oxide semiconductor (MOS) devices [1], in order to meet the crucial requirements such as low power consumption and high switching speed. However, due to certain technological challenges such as leakage current, uncontrolled tunneling, poor electrostatics integrity, and second-order effects, the performance of the downscaled device deteriorates. To overcome these issues and meet the current demands of the industry, several novel device architecture and methodologies are being adopted, where spintronics [2], [3], [4], [5] seems to be the most promising.