Experimental Evidence of t2g Electron-Gas Rashba Interaction Induced by Asymmetric Orbital Hybridization

We report the control of Rashba spin-orbit interaction by tuning asymmetric hybridization between Ti orbitals at the LaAlO3/SrTiO3 interface. This asymmetric orbital hybridization is modulated by introducing a LaFeO3 layer between LaAlO3 and SrTiO3, which alters the Ti-O lattice polarization and traps interfacial charge carriers, resulting in a large Rashba spin-orbit effect at the interface in the absence of an external bias. This observation is verified through high-resolution electron microscopy, magnetotransport and first-principles calculations. Our results open hitherto unexplored avenues of controlling Rashba interaction to design next-generation spin orbitronics.

Automated summary

We have successfully controlled the Rashba spin-orbit interaction by tuning the asymmetric hybridization between Ti orbitals at the LaAlO3/SrTiO3 interface. This was achieved by introducing a LaFeO3 layer, which altered the lattice polarization and trapped charge carriers, resulting in a large Rashba effect at the interface without external bias. Our findings, verified through experimental and computational methods, open new avenues for controlling Rashba interaction and designing next-generation spin orbitronics.