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Tunable Valley and Spin Splittings in VSi2N4 Bilayers
Li Liang1, Ying Yang1, Xiaohui Wang1
1Center for Quantum Transport and Thermal Energy Science, School of Physics and Technology, Nanjing Normal University, Nanjing210023, China.
Researchers demonstrate electric control of valley and spin in VSi2N4 bilayers. This offers a path toward energy-efficient information technologies by tuning electronic properties with electric fields.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Quantum Information
Background:
- Valley and spin degrees of freedom are crucial for advanced information technologies.
- Current methods for controlling these properties often lack energy efficiency.
Purpose of the Study:
- To demonstrate tunable electric control of valley and spin degeneracy splittings in VSi2N4 bilayers.
- To explore the potential for energy-efficient electronic devices.
Main Methods:
- First-principles calculations were employed to investigate VSi2N4 bilayers.
- The effects of interlayer magnetic couplings, stacking orders, and vertical electric fields were analyzed.
Main Results:
- Tunable valley and spin degeneracy splittings were achieved in VSi2N4 bilayers.
- A variety of valley and spin degeneracy combinations were observed based on structural configurations.
- Vertical electric fields allowed for significant tuning of degeneracy splitting magnitude and sign.
- Selective realization of anomalous Hall currents with varied valley and spin indices was demonstrated.
Conclusions:
- VSi2N4 bilayers offer a promising platform for electric control of multiple electronic degrees of freedom.
- The findings provide a practical approach for designing energy-efficient spintronic and valleytronic devices.
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