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Fabricating van der Waals Heterostructures with Precise Rotational Alignment
Published on: July 5, 2019
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Gate-controlled spin-valley-layer locking in bilayer transition-metal dichalcogenides.
1Department of Physics, Kharazmi University, 31979-37551, Tehran, Iran. hoseinkhani01@gmail.com.
Nanoscale
|November 4, 2020
Summary
Researchers demonstrate an electrically controllable platform in bilayer transition metal dichalcogenides (TMDs) for advanced logic devices. This platform enables precise control over electron spin, valley, and layer pseudospin for high-performance electronics.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Nanotechnology
Background:
- Electron internal degrees of freedom are crucial for high-performance electronic devices.
- Bilayer transition metal dichalcogenides (TMDs) exhibit interplay between spin-orbit and interlayer couplings.
- Pseudospintronics offers a new paradigm for electronic device design.
Purpose of the Study:
- To investigate the transport of spin, valley, and layer pseudospin in AB-stacked bilayer TMDs.
- To demonstrate an electrically controllable platform for multifunctional and ultra-high-speed logic devices.
- To determine conditions for excellent spin, valley, and layer polarizations.
Main Methods:
- Theoretical study of electron transport through a magnetoelectric barrier in bilayer TMDs.
- Analysis of spin, valley, and layer pseudospin transport under electric and magnetic fields.
- Investigation of gate-controlled polarization inversion.
Main Results:
- Achieved perfect spin and valley polarizations and good layer localization over a large Fermi energy range.
- Demonstrated electrical control for inverting spin, valley, and layer polarizations using gate potentials.
- Identified conditions for excellent polarizations in terms of adjustable system parameters.
- Showed that a single electric barrier acts as a bipolar pseudospin semiconductor.
Conclusions:
- An electrically controllable platform for multifunctional pseudospintronic devices based on bilayer TMDs has been demonstrated.
- The findings pave the way for novel 2D material-based pseudospintronic applications.
- Precise control over electron spin, valley, and layer pseudospin is achievable.
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