High mobility and directional magnetotransport in (001)- and (110)-oriented two-dimensional electron gas at spin-coated PrAlO3/SrTiO3 interfaces

Two-dimensional electron gas (2DEG) at complex oxide interfaces presents a unique platform to investigate various correlated electron phenomena in low-dimensional environments. While most previous research has focused on (001) oriented 2DEG grown by pulsed laser deposition, we report the fabrication of conducting interfaces between paramagnetic PrAlO3 (PAO) and SrTiO3 (STO) in both (001) and (110) orientations using the spin-coating technique. The 2DEGs exhibit high conductivity, with Hall mobilities of approximately 150 cm2/Vs and 826 cm2/Vs in the (001) and (110) orientations, respectively, at 2 K. Additionally, we observe evidence of the Kondo effect in both samples. Out-of-plane magnetoresistance (MR) analysis confirms the existence of electron-electron interaction in the high-magnetic-field regime, while in-plane MR shows a crossover from weak localization to weak antilocalization for both samples. Notably, we report strong out-of-plane and in-plane directional anisotropy in a spin-coated (110)-2DEG along the in-plane [001] and [11¯0] crystallographic directions. The estimated Rashba spin splitting energy (Δ) for both [001] and [11¯0] directions reveals a maximum difference of Δ[001]−[11¯0]∼0.71 meV at 2 K. Furthermore, spin relaxation in these interfaces follows the D'yakonov-Perel (Rashba spin-orbit coupling) mechanism (τso∝μ−1). This study highlights the remarkable potential of the spin-coating method for producing high-quality oxide 2DEGs. locked icon locked icon locked icon locked icon locked icon locked icon locked icon locked icon locked icon locked icon Physics Subject Headings (PhySH)Anisotropic magnetoresistanceKondo effectWeak antilocalizationWeak localization2-dimensional systemsMagnetization measurementsResistivity measurementsSpin coatingX-ray diffraction