High-Performance Spin Field-Effect Transistors with Multicycle Spin Precession in BLG/WSe₂/hBN Heterostructures

Area of Science:

• Spintronics
• Condensed Matter Physics
• Materials Science

Background:

• Spintronics leverages electron spin for enhanced information processing, addressing conventional electronics limitations.
• The spin-injected field-effect transistor (spin FET) is crucial for spintronics, featuring a semiconducting channel and ferromagnetic electrodes.

Purpose of the Study:

• To present a high-mobility BLG/WSe2/hBN spin FET operating across a wide temperature range.
• To investigate spin transport dynamics and control in 2D heterostructures.

Main Methods:

• Fabrication of a BLG/WSe2/hBN heterostructure spin FET.
• Characterization of spin injection, detection, and precession from cryogenic to room temperature.
• Analysis of spin transport in ballistic, semiballistic, and diffusive regimes.

Main Results:

• Demonstrated efficient spin injection, detection, and precession in the spin FET.
• Observed coherent spin precession in the ballistic regime, transitioning to reduced coherence in other regimes.
• Achieved tunable spin dynamics via gate voltage control of Rashba spin-orbit coupling.

Conclusions:

• The study advances understanding of spin transport in 2D heterostructures.
• The developed spin FET shows potential for electrically controlled spintronic devices.
• Findings support future applications in logic, memory, and quantum technologies.