Electronic and magnetic properties of two dimensional electron gases at complex oxide interfaces for different polar systems and crystallographic orientations

Abstract

The two dimensional electron gas (2DEG) at the prototype LaAlO3/SrTiO3 perovskite oxide interfaces were investigated under various aspects to understand the nature of conductivity, magnetic interactions and interface strain effects. In my work it was shown that 2DEG can also arise at this LaAlO3/SrTiO3 (110) interface which was otherwise unexpected from electrostatic boundary conditions suggest that no conductivity would be expected for the interface along the (110)orientation. The role of the A and B cationic sites of the polar ABO3 layer on interface characteristics were investigated by preparing various polar/non-polar interfaces (NdAlO3/SrTiO3, PrAlO3/SrTiO3 and NdGaO3/SrTiO3). These new interfaces were also found to support the creation of 2DEG. In another study, the effect of proton beam exposure on the LaAlO3/SrTiO3 interface conductivity was studied and it was found that conductivity can be manipulated with ion fluencies by inducing electron localization those results in insulating ground state.