Mapping Rashba and Dresselhaus spin-orbit interactions to inversion asymmetry in perovskite oxide heterostructures

Inversion asymmetry, combined with spin-orbit interaction, leads to Rashba or Dresselhaus effects or combinations that are promising for technologies based on antiferromagnetic spintronics. Since understanding the exact nature of spin-orbit interaction is crucial for developing a technology based on it, mapping the nature of inversion asymmetry with the type of spin-orbit interaction is the key. We simulate the perovskite oxide heterostructure ${\mathrm{LaAlO}}_{3}|{\mathrm{SrIrO}}_{3}|{\mathrm{SrTiO}}_{3}$, preserving the inversion symmetry within density functional theory to demonstrate the relation between the nature of inversion asymmetry and the corresponding Rashba- or Dresselhaus-type interaction. With progressive distortion in the heterostructure, we determine how the structure inversion asymmetry sets in with distorted bond lengths and angles, leading to the Rashba effect in the system in the presence of a microscopic electric field. Further, the introduction of tilted ${\mathrm{IrO}}_{6}$ octahedra leads to bulk inversion asymmetry, helping a combined Rashba-Dresselhaus interaction to occur. A comparison of the spin textures obtained with our density functional theory calculations and theoretical modeling helps us identify the exact nature of the interactions. In the context of perovskite heterostructures, our work demonstrates what types of distortions lead to bulk inversion asymmetry and what other distortions can lead only to structure inversion asymmetry by mapping different types of spin-orbit interactions to different distortions. Additionally, our work emphasizes the importance of spin texture in identifying the nature of spin-orbit interaction. It may serve as a guide for identifying different types of Rashba-like spin-orbit interactions.