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Controllable Valley Polarization Using Silicene Double Line Defects Due to Rashba Spin-Orbit Coupling
Hongyu Tian1, ChongDan Ren2, Benhu Zhou3
1School of Physics and Electronic Engineering, Linyi University, Linyi, 276005, China. tianhongyu@lyu.edu.cn.
Nanoscale Research Letters
|November 29, 2019
Summary
We found that Rashba spin-orbit coupling (RSOC) in silicene creates oscillating transmission. An electric field enables perfect valley polarization for semiconductor valleytronics applications.
Area of Science:
- Condensed matter physics
- Materials science
- Nanotechnology
Background:
- Silicene exhibits unique electronic properties due to its two-dimensional honeycomb structure.
- Spin-orbit coupling (SOC) plays a crucial role in spintronics and valleytronics.
- Rashba spin-orbit coupling (RSOC) can be tuned by external electric fields.
Purpose of the Study:
- To theoretically investigate valley polarization in silicene with parallel line defects.
- To explore the effects of Rashba spin-orbit coupling (RSOC) and perpendicular electric fields on valley polarization.
- To establish a method for generating valley-polarized currents using electrical means.
Main Methods:
- Theoretical investigation of electronic transport in silicene.
- Analysis of transmission coefficients considering intrinsic spin-orbit coupling (SOC) and RSOC.
- Simulation of the impact of perpendicular electric fields on valley polarization.
Main Results:
- RSOC exceeding intrinsic SOC leads to synchronized oscillations in transmission coefficients for both valleys.
- A perpendicular electric field alters oscillation periodicity, creating regions for perfect valley polarization.
- Valley polarizability can be precisely controlled from 1 to -1 via electric field strength.
Conclusions:
- Silicene with line defects offers a tunable platform for valley polarization.
- Electrical control of valley polarization is achievable, paving the way for valleytronics.
- This work provides a novel route for generating valley-polarized currents in semiconductor devices.
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