Karolina Janicka

Metallic and Insulating Oxide Interfaces Controlled by Electronic Correlations

The strength of electronic correlations dictates the transport properties of oxide interfaces. The formation of two-dimensional electron gases (2DEGs) at complex oxide interfaces is directly influenced by the oxide electronic properties. We investigated how local electron correlations control the 2DEG by inserting a single atomic layer of a rare-earth oxide (RO) [(R is lanthanum (La), praseodymium (Pr), neodymium (Nd), samarium (Sm), or yttrium (Y)] into an epitaxial strontium titanate oxide (SrTiO3) matrix using pulsed-laser deposition with atomic layer control. We find that structures with La, Pr, and Nd ions result in conducting 2DEGs at the inserted layer, whereas the structures with Sm or Y ions are insulating. Our local spectroscopic and theoretical results indicate that the interfacial conductivity is dependent on electronic correlations that decay spatially into the SrTiO3 matrix. Such correlation effects can lead to new functionalities in designed heterostructures.

Ferroelectric dead layer driven by a polar interface

Based on first-principles and model calculations we investigate the effect of polar interfaces on the ferroelectric stability of thin-film ferroelectrics. As a representative model, we consider a

Magnetism of LaAlO3∕SrTiO3 superlattices

{\text{TiO}}_{2}

Domain overlap in antiferromagnetically coupled [Co/Pt]/NiO /[Co/Pt] multilayers

-terminated

Effects of magnetostatic coupling on stripe domain structures in magnetic multilayers with perpendicular anisotropy

{\text{BaTiO}}_{3}

Quantum Nature of Two-Dimensional Electron Gas Confinement at LaAlO 3 =SrTiO 3 Interfaces

film with LaO monolayers at the two interfaces that serve as doping layers. We find that the polar interfaces create an intrinsic electric field that is screened by the electron charge leaking into the

Origin of the interlayer exchange coupling in [Co/Pt]/NiO/ [Co/Pt] multilayers studied with XAS, XMCD, and micromagnetic modeling

{\text{BaTiO}}_{3}

Magnetism of LaAlO 3 /SrTiO 3 superlattices

layer. The amount of the leaking charge is controlled by the boundary conditions which are different for three heterostructures considered, namely, vacuum/

Effect of polar interfaces on thin-film ferroelectricity

\text{LaO}/{\text{BaTiO}}_{3}/\text{LaO}

Metal-insulator transition by rare-earth substitution in oxide two-dimensional electron gas

,