Unconventional Shubnikov-de Haas oscillations at the EuO/KTaO₃ interface

The coexistence of electric-field controlled superconductivity and spin-orbit interaction in two-dimensional electron gas (2DEG) based on complex oxides (e.g., SrTiO3 and KTaO3) hold great promise for advancement in spintronics and quantum computing. However, a comprehensive understanding of the electronic structure that gives rise to the multifunctional character of these 2DEG remains elusive.

To address this, we recently investigated Shubnikov-de Haas oscillations in EuO/KTaO3 in high magnetic fields (60 T) and at low temperatures (0.5 K). Remarkably, we observed a progressive increase in cyclotron mass and oscillation frequency with the magnetic field, indicating the presence of non-trivial electronic bands induced by spin-orbit interaction [1]. Besides providing experimental evidence for non-trivial electronic states in oxides-2DEG, these findings shed light on the recent predictions of topological states in the 2DEG based on similar perovskite transition metal oxides.