Strong Rashba parameter of two-dimensional electron gas at CaZrO3/SrTiO3 heterointerface

We synthesized a CaZrO 3 /SrTiO 3 oxide heterostructure, which can serve as an alternative to LaAlO 3 /SrTiO 3 , and confirmed the generation of 2-dimensional electron gas (2-DEG) at the heterointerface. We analyzed the electrical-transport properties of the 2-DEG to elucidate its intrinsic characteristics. Based on the magnetic field dependence of resistance at 2 K, which exhibited Weak Anti-localization (WAL) behaviors, the fitted Rashba parameter values were found to be about 12–15 × 10 –12 eV*m. These values are stronger than the previous reported Rashba parameters obtained from the 2-DEGs in other heterostructure systems and several layered 2D materials. The observed strong spin–orbit coupling (SOC) is attributed to the strong internal electric field generated by the lattice mismatch between the CaZrO 3 layer and SrTiO 3 substrate. This pioneering strong SOC of the 2-DEG at the CaZrO 3 /SrTiO 3 heterointerface may play a pivotal role in the developing future metal oxide-based quantum nanoelectronics devices.