Spin and charge transport in U-shaped one-dimensional channels with spin-orbit couplings

Abstract

A general form of the Hamiltonian for electrons confined to a curved one-dimensional (1D) channel with spin-orbit coupling (SOC) linear in momentum is rederived and is applied to a U-shaped channel. Discretizing the derived continuous 1D Hamiltonian to a tight-binding version, the Landauer-Keldysh formalism (LKF) for nonequilibrium transport can be applied. Spin transport through the U-channel based on the LKF is compared with previous quantum mechanical approaches. The role of a curvature-induced geometric potential which was previously neglected in the literature of the ring issue is also revisited. Transport regimes between nonadiabatic, corresponding to weak SOC or sharp turn, and adiabatic, corresponding to strong SOC or smooth turn, is discussed. Based on the LKF, interesting charge and spin transport properties are further revealed. For the charge transport, the interplay between the Rashba and the linear Dresselhaus (001) SOCs leads to an additional modulation to the local charge density in the half-ring part of the U-channel, which is shown to originate from the angle-dependent spin-orbit potential. For the spin transport, theoretically predicted eigenstates of the Rashba rings, Dresselhaus rings, and the persistent spin-helix state are numerically tested by the present quantum transport calculation.

16 pages, 7 figures

References in corpus (11)

• An Exact SU(2) Symmetry and Persistent Spin Helix in a Spin-Orbit Coupled System
• Emergence of the persistent spin helix in semiconductor quantum wells
• Can Non-Equilibrium Spin Hall Accumulation be Induced in Ballistic Nanostructures?
• Persistent current in ballistic mesoscopic rings with Rashba spin-orbit coupling
• Quantum rings as electron spin beam splitters
• Imaging mesoscopic spin Hall flow: Spatial distribution of local spin currents and spin densities in and out of multiterminal spin-orbit coupled semiconductor nanostructures
• Modulating Unpolarized Current in Quantum Spintronics: Visibility of Spin-Interference Effects in Multichannel Aharonov-Casher Mesoscopic Rings
• Persistent spin helix in Rashba-Dresselhaus two-dimensional electron systems
• Anisotropic spin transport in two-terminal mesoscopic rings: the Rashba and Dresselhaus spin-orbit interactions
• Non-Abelian spin-orbit gauge: Persistent spin helix and quantum square ring
• Nonuniform Rashba-Dresselhaus spin precession along arbitrary paths

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• Spin-deformation coupling in two-dimensional polar materials
• Curvature induced out of plane spin accumulation
• Higher Chern Number States in Curved Periodic Nanowires