Evanescent states in 2D electron systems with spin-orbit interaction and spin-dependent transmission through a barrier

Abstract

We find that the total spectrum of electron states in a bounded 2D electron gas with spin-orbit interaction contains two types of evanescent states lying in different energy ranges. The first-type states fill in a gap, which opens in the band of propagating spin-splitted states if tangential momentum is nonzero. They are described by a pure imaginary wavevector. The states of second type lie in the forbidden band. They are described by a complex wavevector. These states give rise to unusual features of the electron transmission through a lateral potential barrier with spin-orbit interaction, such as an oscillatory dependence of the tunneling coefficient on the barrier width and electron energy. But of most interest is the spin polarization of an unpolarized incident electron flow. Particularly, the transmitted electron current acquires spin polarization even if the distribution function of incident electrons is symmetric with respect to the transverse momentum. The polarization efficiency is an oscillatory function of the barrier width. Spin filtering is most effective, if the Fermi energy is close to the barrier height.

9 pages, 9 figures, more general boundary conditions are used, typos corrected

References in corpus (21)

• Spintronics: Fundamentals and applications
• Universal Intrinsic Spin-Hall Effect
• On A Proper Definition of Spin Current
• Spin Accumulation in Quantum Wires with Strong Rashba Spin-Orbit Coupling
• Spin-dependent tunnelling through a symmetric barrier
• The Rashba Hamiltonian and electron transport
• Spin polarization of electrons by non-magnetic heterostructures : basics of spin-optics
• Spin-Hall conductivity due to Rashba spin-orbit interaction in disordered systems
• Spin Hall Effect
• Spin-orbit coupling and spin transport
• Large Bychkov-Rashba spin-orbit coupling in high-mobility GaN/AlGaN heterostructures
• Spin Accumulation and Equilibrium Currents at the Edge of 2DEGs with Spin-Orbit Coupling
• Tunneling spin-galvanic effect
• Spin-dependent tunneling through a symmetric semiconductor barrier: the Dresselhaus effect
• Spin Hall effect in clean two dimensional electron gases with Rashba spin-orbit coupling
• Polarized Electric Current in Semiclassical Transport with Spin-Orbit Interaction
• Spin-dependent transport of electrons in the presence of smooth lateral barrier and spin-orbit interaction
• Spin Polarization via Electron Tunneling through an Indirect-Gap Semiconductor Barrier
• Charge and spin density modulations in semiconductor quantum wires
• Spin tunneling through an indirect barrier
• Diffuse emission in the presence of inhomogeneous spin-orbit interaction for the purpose of spin filtration

Cited by in corpus (16)

• Transport signature of fractional Fermions in Rashba nanowires
• Equilibrium edge spin currents in two-dimensional electron systems with spin-orbit interaction
• Spin-dependent tunneling into an empty lateral quantum dot
• Goos-Hänchen shifts in spin-orbit-coupled cold atoms
• Interplay between resonant tunneling and spin precession oscillations in all-electric all-semiconductor spin transistors
• Tunneling conductance in two-dimensional junctions between a normal metal and a ferromagnetic Rashba metal
• Spin dynamics in tunneling decay of a metastable state
• Spin polarization of electron current through a potential barrier in two-dimensional structures with spin-orbit interaction
• Spin Filtering via Resonant Reflection of Relativistic Surface States
• Bound states of spin-orbit coupled cold atoms in a Dirac delta-function potential
• Unidirectional spin transport of a spin-orbit-coupled atomic matter wave using a moving Dirac $\delta$-potential well
• Spin-sensitive atom mirror via spin-orbit interaction
• Unconventional gate voltage dependence of the charge conductance caused by spin-splitting Fermi surface by Rashba-type spin-orbit coupling
• Spin currents in a normal two-dimensional electron gas in contact with a spin-orbit interaction region
• Spin-dependent Scattering by a Potential Barrier on a Nanotube
• Interface states in two-dimensional electron systems with spin-orbital interaction