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We present a theoretical investigation on wave-vector filtering (WVF) effect for electrons in an antiparallel asymmetric double δ-magnetic-barrier nanostructure, which can be realized experimentally by patterning two asymmetric ferromagnetic (FM) stripes on top and bottom of GaAs/AlxGa1-xAs heterostructure, respectively. It is shown that a considerable WVF effect appears due to an essentially two-dimensional (2D) process for electrons across this nanostructure. It is also shown that WVF efficiency is associated with incident energy, incident direction and structural parameters. In particular, WVF efficiency can be tuned by applying a negative voltage, which maybe results in an electrically-controllable electron-momentum filter for nanoelectronics device applications.

We report a theoretical investigation on effect of a δ-doping on spin-dependent dwell time for electron in embedded magnetic-electric-barrier nanostructure (EMEBN), which is fabricated by depositing a ferromagnetic stripe and a Schottky-metal stripe on top and bottom of InAs/AlxIn1−xAs heterostructure, respectively. Dwell time still remains spin related after a δ-doping is comprised in EMEBN by atomic-layer doping. Moreover, due to a δ-doping dependent effective potential experienced by electron in this EMEBN, both magnitude and sign of spin-polarized dwell time can be controlled by changing δ-doping. Therefore, this EMEBN can serve as a controllable temporal spin splitter for spintronics device applications.

We theoretically explore how to manipulate electron-spin polarization by a δ-potential in an embedded magnetic-electric-barrier microstructure (EMEBM), which can be fabricated experimentally by patterning a ferromagnetic (FM) stripe and a Schottky-metal (SM) stripe on top and bottom of GaAs/AlxGa1_xAs heterostructure, respectively. Due to spin-orbit coupling (SOC) an appreciable electron-spin polarization effect still remains, even through a δ-potential is contained. Besides, electron-spin polarization ratio can be controlled by δ-potential, which may result in a structurally-manipulable electron-spin filter for spintronics device applications.

We theoretically investigate spin polarization for electrons in magnetically and electrically confined semiconductor microstructure, which is constructed by patterning a ferromagnetic stripe and a Schottky-metal stripe on top and bottom of GaAs/AlxGa1-xAs heterostructure, respectively. Both Zeeman interaction and spin–orbit coupling are taken into account; however, electron-spin polarization comes mainly from the latter due to a small effective g-factor for GaAs. Besides, both magnitude and sign of spin polarization can be manipulated by changing interfacial confining electric field or strain engineering, resulting in a tunable electron-spin filter for spintronics device applications.

We theoretically explore the manipulation of a temporal electron-spin splitter by a δ-potential in an embedded magnetic-electric-barrier microstructure (EMEBM), which is constructed by patterning a ferromagnetic stripe and a Schottky-metal stripe on the top and bottom of an InAs/Al x In1−x As heterostructure, respectively. Spin polarization of the dwell time remains, even though a δ-potential is inserted by atomic-layer doping. Both the magnitude and sign of the spin-polarized dwell time can be manipulated by changing the weight or position of the δ-potential. Thus, a structurally controllable temporal electron-spin splitter can be obtained for spintronics device applications.

We theoretically investigate wave-vector filtering (WVF) effect for electrons in an antiparallel asymmetric double δ-magnetic-barrier microstructure under a bias, which can be fabricated experimentally by patterning two asymmetric ferromagnetic (FM) stripes on top and bottom of GaAs/AlxGa1-xAs heterostructure, respectively. It is found that an appreciable WVF effect appears because of an essentially two-dimensional (2D) process for electrons across this microstructure. WVF effect is found to be sensitive to applied bias. WVF efficiency can be tuned by changing bias, which may lead to an electrically-controllable momentum filter for nanoelectronics device applications.

Based on antiparallel asymmetric double δ-magnetic-barrier semiconductor microstructure constructed on the surface of GaAs/Al1-xGaxAs heterostructure by patterning two ferromagnetic stripes, an electron-momentum filter was proposed recently. We further explore the effect of a δ-potential realized by the atomic-layer doping technique on this filter device. It is shown that this filter is sensitive to the δ-potential because the effective potential experienced by electrons in the device depends on the δ-potential. It is also shown that both magnitude and sign of wave-vector filtering efficiency can be tuned by adjusting weight or position of the δ-potential. Therefore, a controllable electron-momentum filter may be obtained for nanoelectronics device applications.