Fully Spin-Polarized Current in Gated Bilayer Silicene

TL;DR

This paper predicts that gated bilayer silicene can produce fully spin-polarized current without magnetic fields, leveraging its antiferromagnetic ground state and electric field tuning, offering a new approach for spintronics.

Contribution

It introduces a novel method to generate fully spin-polarized current in bilayer silicene using electric fields, without magnetic materials or external magnetic fields.

Findings

Bilayer silicene can be antiferromagnetic at certain interlayer distances.

Applying an out-of-plane electric field induces half-metallicity at low doping.

Fully spin-polarized current can be achieved without magnetic fields or doped magnetic ions.

Abstract

By applying density functional theory calculations, we predict that the groundstate of bilayer silicene at certain interlayer distances can be antiferromagnetic. At small electron or hole doping, it becomes half metallic under applied out-of-plane electric field, which can be used to produce fully spin-polarized field-effect-driven current even in the absence of external magnetic field, ferromagnetic substrates, doped magnetic ions, or spin-orbital coupling. Our finding points out a new route to overcome the major challenge of spintronics.