Optical Manipulation of Rashba Spin-Orbit Coupling at SrTiO₃-Based Oxide Interfaces.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Spintronics

Background:

• Spin-orbit coupling (SOC) is vital for spintronics.
• SrTiO3-based interfaces are promising for electronic applications.
• Tunable SOC is key for advanced spintronic devices.

Purpose of the Study:

• To demonstrate photoinduced charge doping for tunable Rashba SOC at SrTiO3 interfaces.
• To investigate the nonvolatile and erasable nature of optical gating.
• To explore the transition from weak localization to weak antilocalization via optical manipulation.

Main Methods:

• Utilizing optical gating (photoinduced charge doping) to tune Rashba SOC.
• Investigating the effect of illumination wavelengths and gate voltages.
• Analyzing conductivity changes and their correlation with SOC strength.
• Observing the interference of Bloch wave functions.

Main Results:

• Rashba SOC at SrTiO3 interfaces is highly tunable by optical gating.
• Optical manipulation is nonvolatile and erasable via warming-cooling cycles.
• SOC strength exhibits an upward-downward trend with increasing conductivity due to orbital hybridization.
• Optical gating induces a transition from weak localization to weak antilocalization.

Conclusions:

• Photoinduced charge doping offers a novel, nonvolatile method for tuning SOC.
• The findings enable the exploration of photoinduced nontrivial quantum states.
• This research paves the way for designing optically controlled spintronic devices.