Strain-Induced Giant Topological Rashba Splitting.

Area of Science:

• Condensed Matter Physics
• Materials Science
• Quantum Mechanics

Background:

• Rashba-type spin-orbit coupling is crucial for spintronic devices.
• Enhancing Rashba splitting typically involves increasing ferroelectric polarization.
• Existing methods often face limitations in maximizing spin-orbit coupling effects.

Purpose of the Study:

• To explore a novel mechanism for enhancing Rashba splitting using strain-induced topological band inversion.
• To investigate the impact of strain on ferroelectric chalcogenides like BaTiSe3 and BaZrSe3.
• To identify materials with significantly enhanced Rashba parameters for spintronics.

Main Methods:

• Density Functional Theory (DFT) calculations were employed.
• Monolayer quasi-1D ferroelectric chalcogenides (BaTiSe3, BaZrSe3) were modeled.
• The effects of compressive biaxial strain on electronic band structure and spin texture were analyzed.

Main Results:

• Monolayer BaTiSe3 and BaZrSe3 exhibit in-plane polarization and Rashba splitting.
• A 1% compressive strain on BaZrSe3 significantly enhances the Rashba parameter (~3.0 eV Å) and splitting energy (~60 meV).
• Strain induces a topological phase transition, leading to a giant Berry curvature (~1400 Ų).

Conclusions:

• Strain-induced topological band inversion offers a powerful route to enhance Rashba splitting in 2D ferroelectrics.
• The findings reveal a unique interplay between topology and ferroelectricity under strain.
• This approach provides promising avenues for advancing spintronics technology through optimized spin-orbit coupling.