Related Experiment Video
Updated: Aug 12, 2026
10:36
Electric-field Control of Electronic States in WS2 Nanodevices by Electrolyte Gating
Published on: April 12, 2018
Electrostatically Tunable and Topological-Edge-States-Associated Spin-Charge Conversion in Bilayer WTe2
Xin Chen1, Tao Hou2,3, Wanghao Tian1
1School of Electrical and Electronic Engineering, Nanyang Technological University, Singapore, Singapore.
Small (Weinheim an Der Bergstrasse, Germany)
|August 11, 2026
Summary
Researchers demonstrate tunable spin-charge conversion in bilayer WTe2, utilizing residual topological edge states. This breakthrough enhances spin-charge conversion efficiency and allows electrostatic modulation for advanced spintronic devices.
Area of Science:
- Condensed Matter Physics
- Materials Science
- Spintronics
Background:
- Topological edge/surface states offer efficient spin-charge conversion crucial for low-power spintronics.
- Electrostatic tunability is essential for spintronic devices but challenging with typical gapless topological states.
Purpose of the Study:
- To investigate electrostatically tunable spin-charge conversion in bilayer Tungsten Ditelluride (WTe2).
- To explore the role of residual topological edge states in enhancing and tuning spin-charge conversion.
Main Methods:
- Experimental fabrication and characterization of bilayer WTe2 devices.
- Comparison with thicker WTe2 reference devices.
- Theoretical calculations of edge-state properties and spin Hall conductance.
Main Results:
- Bilayer WTe2 shows an order-of-magnitude enhancement in spin-charge conversion efficiency compared to thicker WTe2.
- Conversion efficiency is significantly modulated by gate voltages.
- Theoretical calculations confirm residual topological edge states with spin-momentum locking in bilayer WTe2.
Conclusions:
- Partially preserved topological edge states in bilayer WTe2 significantly enhance and enable electrostatic tunability of spin-charge conversion.
- This work presents a potential pathway for developing gate-reconfigurable van der Waals spintronic devices.
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