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In this paper, we theoretically investigate how to control spin filtering via a [Formula: see text]-doping for electrons in a magnetically and electrically modulated semiconductor nanostructure (MEMSN), which can be realized by patterning a ferromagnetic (FM) stripe and a Schottky-metal (SM) stripe on top and bottom of GaAs/AlxGa[Formula: see text]As heterostructure in experiments, respectively. A considerable spin filtering effect still exists because of spin–orbit coupling (SOC), even if a [Formula: see text]-doping is included. Moreover, spin polarization ratio can be manipulated by [Formula: see text]-doping, which may lead to a structurally-controllable electron-spin filter for semiconductor spintronics.

We theoretically explore how to control electron-spin polarization in layered semiconductor nanostructure (LSN) by a [Formula: see text]-potential realized by atomic-layer doping. Due to Rashba spin-orbit coupling, a considerable spin polarization still remains even through a [Formula: see text]-potential is embedded in the LSN. Spin polarization ratio can be controlled by altering weight or position of [Formula: see text]-potential. Based on such an LSN, a structurally-tunable electron-spin filter may be obtained for spintronics device applications.

Spin-polarized Goos-Hanchen (GH) displacement is calculated for electrons in a hybrid magnetic-electric-barrier (MEB) nanostructure modulated by spin-orbit couplings (SOCs), which can be realized experimentally by the deposition of a ferromagnetic (FM) stripe and a Schottky-metal (SM) stripe in parallel configuration on the top of the GaAs/AlxGa1-xAs heterostructure. Both Zeeman interaction (ZI) and SOC are taken into account. It is shown that ZI has less contribution to spin-polarized GH displacement than SOC due to a small g-factor for GaAs. It is also shown that spin-polarized GH displacement can be controlled by Rashba or Dresselhause SOC --interfacial confining electric field or strain engineering, which results hence in a tunable spatial spin splitter for spintronics device applications.

Spin-dependent Goos–Hanchen（GH）effect of the electron in a magnetic barrier nanostructure modulated by the spin-orbit coupling (SOC) is investigated. Two kinds of intrinsic SOCs (Rashba and Dresselhaus types) are taken into account, and spin-dependent lateral shifts are obtained by the transfer matrix method and the stationary phase approximation. The spin-dependent lateral shift is found to be related closely to the SOC. Both magnitude and sign of the spin-polarised lateral shift can be controlled by properly adjusting the strength of Rashba or Dresselhaus SOC. These interesting features can provide an alternative approach to manipulate spin-polarised electrons in the semiconductor, and such a nanostructure can serve as a controllable spatial spin splitter for spintronics applications.

We report on a theoretical study of the giant magnetoresistance (GMR) effect in a δ -doped magnetically confined semiconductor heterostructure nanostructure (MCSHN), which can be realized by depositing two nanosized ferromagnetic (FM) stripes on top and bottom of the semiconductor heterostructure and using the atomic layer doping technique. It is shown that such a nanosystem shows up a sizable GMR effect due to a significant discrepancy in transmission of parallel (P) and antiparallel (AP) magnetization configurations. It is also shown that the MR ratio varies sensitively with the weight and/or position of the δ -doping. Thus, one can conveniently tailor the degree of GMR effect by tuning the δ -doping, and such a nanosystem can be employed as a controllable GMR device for magnetic information storage.

We report on a theoretical study of magnetoresistance (MR) effect in a magnetically modulated semiconductor heterostructure (MMSH) under an applied bias, which can be constructed on surface of [Formula: see text] heterostructure by depositing two asymmetric ferromagnetic (FM) stripes. Bias-dependent transmission and conductance are calculated numerically, on the basis of both improved transfer matrix method (ITMM) and Landauer–Büttiker conductance theory. An obvious MR effect appears because of a significant difference of transmission between parallel and antiparallel (AP) magnetization configurations. Moreover, MR ratio can be tuned by the bias. These interesting features not only provide an alternative way to manipulate MR effect, but also may lead to an electrically-controllable MR device.

We theoretically investigate how to manipulate the wave vector filtering effect by a traverse electric field for electrons across a hybrid magnetic-electric-barrier nanostructure, which can be experimentally realized by depositing a ferromagnetic stripe and a Schottky-metal stripe on top and bottom of a GaAs/Al x Ga1−xAs heterostructure, respectively. The wave vector filtering effect is found to be related closely to the applied electric field. Moreover, the wave vector filtering efficiency can be manipulated by changing direction or adjusting strength of the traverse electric field. Therefore, such a nanostructure can be employed as an electrically controllable electron-momentum filter for nanoelectronics applications.

We report a theoretical study on spin-polarized lateral displacement for the electron across a magnetic nanostructure with a zero average magnetic field, which can be experimentally realized by depositing a ferromagnetic stripe with a plumb magnetization on the top of a semiconductor heterostructure. It is shown that, the lateral displacement depends strongly on the electron spins due to the Zeeman coupling and the intrinsic symmetry, though the average magnetic field is vanishing in the nanostructure. It is also shown that the spin-polarized lateral displacement is related closely to the structural parameters. Therefore, such a novel magnetic nanostructure may be used as a spin spatial splitter for spintronics applications.

We theoretically investigate how to manipulate spin-dependent Goos–Hanchen (GH) shifts by an applied bias in a realistic magnetic-barrier nanostructure, which is experimentally created by depositing a ferromagnetic stripe with perpendicular magnetization on the top of heterostructure. GH shifts of transmitted electron beams are calculated numerically with the help of the stationary phase method. It is shown that both magnitude and sign of spin polarization in GH shifts are closely relative to the applied bias, which can give rise to a bias-controllable spin beam splitter.

We investigate Goos–Hanchen (GH) effect of spin beams in antiparallel double δ -magnetic-barrier (MB) nanostructure under an applied bias, which can be experimentally realized by depositing two metallic ferromagnetic (FM) stripes on top and bottom of the semiconductor heterostructure. GH shifts for spin beams accross this device, is numerically calculated, with the help of the stationary phase method. It is shown that a sizable spin polarization of GH shifts still exists in this device under an applied bias. It also is shown that both magnitude and sign of spin polarization of GH shifts can be controlled by adjusting the applied bias. These interesting properties may provide an effective approach to spin injection, and this device can be used as a bias-controllable spin beam splitter.

We study how the transmission properties of a two-dimensional electron gas, modulated by a ferromagnetic stripe and a Schottky metal (SM) stripe in a parallel configuration, can be modified by manipulating the voltage applied to the SM stripe. Both the transmission coefficient and conductance of the device are found to be strongly dependent on the electric-barrier height induced by an applied voltage under the SM stripe. Thus, transmission properties of electrons in the device can be conveniently tailored by means of tuning this applied voltage.

We investigate the Goos–Hanchen (GH) effect of spin electron beams in a magnetic-barrier (MB) nanostructure consisting of antiparallel double δ - MBs , which can be experimentally realized by depositing two ferromagnetic (FM) stripes on top and bottom of the semiconductor heterostructure. GH shifts for spin electron beams across this type of MB nanostructures, is derived exactly, with the help of the stationary phase method. It is shown that GH shifts depend strongly on the spin directions for double δ - MBs with unidentical magnetic strengths, giving rise to a considerable spin polarization effect. It also is shown that spin polarization of GH shifts is closely relative to the separation and magnetic-strength difference of two δ - MBs . These interesting properties may provide an alternative scheme to spin-polarize electrons into the semiconductor, and the devices can serve as tunable spin beam splitters.

We propose a scheme to realize electron-spin filtering based on generic ferromagnetic and semiconductor hybrid nanosystem, which can be experimentally realized by depositing a magnetized ferromagnetic stripe with arbitrary magnetization direction on the surface of a semiconductor heterostructure. It is shown that large spin-polarized current can be achieved in the device, which may provide an alternative scheme to spin-polarize electrons into semiconductors and such a device may be used as an electron-spin filter.

The GMR effect in magnetic–electric barrier nanostructure, which can be realized experimentally by depositing two parallel metallic ferromagnetic strips with an applied voltage on the top of heterostructure, is investigated theoretically. It is shown that a considerable GMR effect can be achieved in such nanosystems due to the significant transmission difference for electrons tunneling through parallel and antiparallel magnetization configurations. It is also shown that the magnetoresistance ratio is strongly dependent upon the applied voltage to metallic ferromagnetic strips in nanosystems, thus may leading to voltage-tunable GMR devices.

We theoretically investigate the giant magnetoresistance (GMR) effect in general magnetically modulated semiconductor nanosystems, which can be realized experimentally by depositing two parallel ferromagnetic strips on the top of a heterostructure. Here the exact magnetic profiles and arbitrary magnetization direction of ferromagnetic strips are emphasized. It is shown that a considerable GMR effect can be achieved in such nanosystems due to the significant transmission difference for electrons tunneling through parallel and antiparallel magnetization configurations. It is also shown that the magnetoresistance ratio is strongly influenced by the magnetization direction of ferromagnetic strips in nanosystems, thus possibly leading to tunable GMR devices.

We present a theoretical study of spin-dependent electron transport in an antiparallel double @d-magnetic-barrier nanostructure with an applied bias. It is shown that large spin-polarized current can be achieved in such a device with unidentical strength between two @d-magnetic-barriers. It also is shown that the degree of electron-spin polarization is strongly dependent upon the applied bias. These interesting properties may provide an alternative scheme to spin-polarize electrons into semiconductors, and this device may be used as a bias-tunable spin filter.

We propose a giant magnetoresistance (GMR) device, which can be experimentally realized by depositing two ferromagnetic (FM) strips and a Schottky metal (SM) stripe in parallel configuration on top of the GaAs heterostructure. The GMR effect ascribes a significant electron transmission difference between the parallel and antiparallel magnetization configurations of two FM stripes. Moreover, the MR ratio depends strongly on the magnetic strength of the magnetic barrier (MB) and the electric barrier (EB) height induced by an applied voltage to the SM stripe. Thus, this system can be used as a GMR device with tunable MR by an applied voltage to SM stripe or by magnetic strength of the MB.

A magnetoresistance (MR) device was proposed by depositing two nanosized ferromagnetic strips on top and bottom of the semiconductor heterostructure. For the sake of manipulating its performance, we introduce a tunable [Formula: see text]-potential into this device with the help of the atomic-layer doping technique such as molecular beam epitaxy (MBE) or metal-organic chemical-vapor deposition (MOCVD). We investigate theoretically the impact of the [Formula: see text]-doping on the magnetoresistance ratio (MMRR) of the MR device. Although the [Formula: see text]-doping is embedded in the device, a considerable MR effect still exists due to different transmissions for the electron across parallel (P) and antiparallel (AP) configurations. Moreover, its MMRR varies sensitively with the magnitude and/or position of the [Formula: see text]-doping. Such an MR device can be controlled by changing the [Formula: see text]-doping, resulting in an adjustable MR device for magnetoelectronics applications.