Enhancement of polarization in a spin-orbit coupling quantum wire with a constriction

Abstract

We investigate the enhancement of spin polarization in a quantum wire in the presence of a constriction and a spin-orbit coupling segment. It is shown that the spin-filtering effect is significantly heightened in comparison with the configuration without the constriction. It is understood in the studies that the constriction structure plays a critical role in enhancing the spin filtering by means of confining the incident electrons to occupy one channel only while the outgoing electrons occupy two channels. The enhancement of spin-filtering has also been analyzed within the perturbation theory. Because the spin polarization arises mainly from the scattering between the constriction and the segment with spin-orbit coupling, the sub-band mixing induced by spin-orbit interaction in the scattering process and the interferences result in higher spin-filtering effect.

8 pages, 7 figures

References in corpus (8)

• Ballistic spin-polarized transport and Rashba spin precession in semiconductor nanowires
• Pure spin currents and associated electrical voltage
• Spin-current modulation and square-wave transmission through periodically stubbed electron waveguides
• T-shaped spin filter with a ring resonator
• A prohibition of equilibrium spin currents in multi-terminal ballistic devices
• Spin polarization in a T-shape conductor induced by strong Rashba spin-orbit coupling
• Non-equilibrium spin polarization effects in spin-orbit coupling system and contacting metallic leads
• Spin polarization effects in a two dimensional mesoscopic electronic structure with Rashba spin-orbit and lateral confinement

Cited by in corpus (6)

• Spin polarized current generation from quantum dots without magnetic fields
• Multichannel effects in Rashba quantum wires
• Spin transistor operation driven by the Rashba spin-orbit coupling in the gated nanowire
• Charge and spin current in a quasi-one-dimensional quantum wire with spin-orbit coupling
• Spin-current quantization in a quantum point contact with spin-orbit interaction
• Spin polarization direction switch based on an asymmetrical quantum wire