Spin-dependent transport properties of fully epitaxial Co2MnSi/MgO/Co50Fe50 tunnel junctions

The spin-dependent transport properties of Cu/EuO-based tunnel junctions are investigated by means of the first-principle calculations combined with the non-equilibrium Green’s function (NEGF) method. It is found that the Cu/EuO-based junctions exhibit excellent spin-filtering effect. Furthermore, the mixed Cu/O layer enhances the tunneling of the majority spin through the EuO barrier for the junctions with Cu/O layers due to the fact that the valance-band maximum of the Eu-4[Formula: see text] states shifts to high energies with respect to the Fermi level for these junctions. These results permit the existence of the mixed Cu/O layer in Cu/EuO-based tunnel junctions and promote future applications of these tunnel junctions in spintronic devices.

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Strain Investigation on Spin-Dependent Transport Properties of γ-Graphyne Nanoribbon Between Gold Electrodes

Nanoscale Research Letters ◽

10.1186/s11671-020-03461-3 ◽

2021 ◽

Vol 16 (1) ◽

Author(s):

Yun Li ◽

Xiaobo Li ◽

Shidong Zhang ◽

Liemao Cao ◽

Fangping Ouyang ◽

...

Keyword(s):

Transport Properties ◽

High Performance ◽

Density Functional ◽

Strain Engineering ◽

Molecular Junctions ◽

Spin Splitting ◽

Functional Theory ◽

Spin Dependent Transport ◽

The Density Functional Theory ◽

Dependent Transport

AbstractStrain engineering has become one of the effective methods to tune the electronic structures of materials, which can be introduced into the molecular junction to induce some unique physical effects. The various γ-graphyne nanoribbons (γ-GYNRs) embedded between gold (Au) electrodes with strain controlling have been designed, involving the calculation of the spin-dependent transport properties by employing the density functional theory. Our calculated results exhibit that the presence of strain has a great effect on transport properties of molecular junctions, which can obviously enhance the coupling between the γ-GYNR and Au electrodes. We find that the current flowing through the strained nanojunction is larger than that of the unstrained one. What is more, the length and strained shape of the γ-GYNR serves as the important factors which affect the transport properties of molecular junctions. Simultaneously, the phenomenon of spin-splitting occurs after introducing strain into nanojunction, implying that strain engineering may be a new means to regulate the electron spin. Our work can provide theoretical basis for designing of high performance graphyne-based devices in the future.

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Nanodevices engineering and spin transport properties of MnBi2Te4 monolayer

npj Computational Materials ◽

10.1038/s41524-021-00513-9 ◽

2021 ◽

Vol 7 (1) ◽

Author(s):

Yipeng An ◽

Kun Wang ◽

Shijing Gong ◽

Yusheng Hou ◽

Chunlan Ma ◽

...

Keyword(s):

Transport Properties ◽

Field Effect Transistors ◽

First Principles Calculations ◽

Next Generation ◽

Strong Response ◽

The Road ◽

Spin Dependent Transport ◽

2D Structure ◽

Filtering Effect ◽

Dependent Transport

AbstractTwo-dimensional (2D) magnetic materials are essential for the development of the next-generation spintronic technologies. Recently, layered van der Waals (vdW) compound MnBi2Te4 (MBT) has attracted great interest, and its 2D structure has been reported to host coexisting magnetism and topology. Here, we design several conceptual nanodevices based on MBT monolayer (MBT-ML) and reveal their spin-dependent transport properties by means of the first-principles calculations. The pn-junction diodes and sub-3-nm pin-junction field-effect transistors (FETs) show a strong rectifying effect and a spin filtering effect, with an ideality factor n close to 1 even at a reasonably high temperature. In addition, the pip- and nin-junction FETs give an interesting negative differential resistive (NDR) effect. The gate voltages can tune currents through these FETs in a large range. Furthermore, the MBT-ML has a strong response to light. Our results uncover the multifunctional nature of MBT-ML, pave the road for its applications in diverse next-generation semiconductor spin electric devices.

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