The 2D electron gas (2DEG) formed at the LaXO 3/ SrTiO 3( X = Al , Ti ) oxide interface appears inhomogeneous in several experiments. In particular, we discuss evidences of electron inhomogeneities provided by the phenomenology of the superconducting (SC) phase, which occurs when the carrier density is tuned above a critical value by means of gating, and of the superconductor-to-metal transition driven by gate voltage or magnetic field. The measured resistance and superfluid density result from the percolative connection of superconducting "puddles" with randomly distributed critical temperatures, embedded in a weakly localizing metallic matrix. We propose a possible intrinsic origin of the electron inhomogeneity, resulting from the strong Rashba spin–orbit coupling (RSOC) measured at these oxide interfaces.
Tunable Rashba spin-orbit coupling and its interplay with multiorbital effect and magnetic ordering at oxide interfaces
