Electronic, magnetic and optical properties of atomically controlled complex oxide heterostructures and interfaces

Abstract

The main objective of this thesis is to explore and understand possible new phenomena in various oxide heterostructures based on high quality LaAlO3 and La0.5Sr0.5TiO3 (LSTO) films grown layer-by-layer by Pulsed Laser Deposition (PLD) on various single-terminated substrates with the help of in-situ Reflection High Energy Electron Diffraction (RHEED). In this thesis, electrical magnetoresistance study, magnetic magnetization study and ultrafast optical study were performed on LaAlO3/SrTiO3 (LAO/STO) interfaces and electrical transport study was performed on LSTO films. Especially, the intriguing electronic phase separation was for the first time observed in the LAO/STO interface. These results provide insight into the possible driving mechanisms of the emerging properties at oxide interfaces and demonstrate a novel conducting system with potentially new physics and possible applications.