Tunable Spin and Orbital Edelstein Effect at (111) LaAlO₃/SrTiO₃ Interface.

Area of Science:

• Spintronics
• Condensed Matter Physics
• Materials Science

Background:

• Spintronics utilizes the conversion of charge current to spin current, often through the Edelstein effect.
• The Edelstein effect generates magnetization from an electric field in systems lacking inversion symmetry.
• Oxide heterostructures, with strong spin-orbit coupling and broken inversion symmetry, are ideal for studying these phenomena.

Purpose of the Study:

• To investigate the spin and orbital Edelstein effects at the (111) LaAlO3/SrTiO3 interface.
• To predict and quantify the orbital Edelstein effect in this specific oxide heterostructure.
• To understand the underlying mechanisms governing the Edelstein response, particularly the role of electronic band hybridization.

Main Methods:

• Modeling the LaAlO3/SrTiO3 interface as a bilayer of t2g orbitals using a tight-binding approach.
• Calculating transport properties via the Boltzmann approach.
• Developing an effective model at low filling to explain the Edelstein response behavior.

Main Results:

• Prediction of a gate-tunable spin Edelstein effect.
• Observation of an orbital Edelstein effect an order of magnitude larger than the spin Edelstein effect at low and high electron fillings.
• Identification of crucial impact of electronic band hybridization on Edelstein susceptibility.

Conclusions:

• The (111) LaAlO3/SrTiO3 interface exhibits a significant orbital Edelstein effect, surpassing the spin Edelstein effect.
• Electronic band hybridization plays a critical role in determining the Edelstein response in these oxide heterostructures.
• These findings highlight the potential of oxide heterostructures for advanced spintronic applications.