All-Electrical Generation of Spin-Polarized Currents in Quantum Spin Hall Insulators
arXiv:1612.06629 · doi:10.1103/PhysRevB.95.121407
Abstract
The control and generation of spin-polarized currents (SPCs) without magnetic materials and external magnetic field is a big challenge in spintronics and normally requires spin-flip mechanism. In this work, we propose a novel method to control and generate SPCs in stanene nanoribbons in the quantum spin Hall (QSH) insulator regime by all electrical means without spin-flip mechanism. This is achieved with intrinsic spin-orbit coupling in stanene nanoribbons by tuning the relative phase of spin up and down electrons using a gate voltage, which creates a time delay between them thereby producing alternative SPCs driven by ac voltage. The control and generation of SPCs are demonstrated numerically for ac transport in both transient and ac regime. Our results are robust against edge imperfections and generally valid for other QSH insulators such as silicene and germanene, etc. These findings establish a novel route for generating SPCs by purely electrical means and open the door for new applications of semiconductor spintronics.
5 pages, 4 figures
References in corpus (11)
- Quantum Spin Hall Effect and Topological Phase Transition in HgTe Quantum Wells
- Germanene: a novel two-dimensional Germanium allotrope akin to Graphene and Silicene
- Spin-orbit gap of graphene: First-principles calculations
- Edge state on hydrogen-terminated graphite edges investigated by scanning tunneling microscopy
- All-electric all-semiconductor spin field effect transistors
- Spin Current Generation and Detection in the Presence of AC Gate
- Symmetries of quantum transport with Rashba spin-orbit: Graphene spintronics
- Generation of spin current and polarization under dynamic gate control of spin-orbit interaction in low-dimensional semiconductor systems
- Photoexcitation of electron wave packets in quantum spin Hall edge states: effects of chiral anomaly from a localised electric pulse
- Pure spin current generation in a Rashba-Dresselhaus quantum channel
- Opposite spin accumulations on the transverse edges by the confining potential