Impact Factor:0.0
DOI number:10.1103/PhysRevMaterials.4.115002
Affiliation of Author(s):American Physical Society
Journal:Physical Review Materials
Abstract:The discovery of a two-dimensional electron system (2DES) at the interfaces of perovskite oxides such as LaAlO3 and SrTiO3 has motivated enormous efforts in engineering interfacial functionalities with this type of oxide heterostructures. However, the fundamental origins of the 2DES are still not understood, e.g., the microscopic mechanisms of coexisting interface conductivity and magnetism. Here we report a comprehensive spectroscopic investigation on the depth profile of 2DES-relevant Ti3d interface carriers using depth- and element-specific techniques like standing-wave excited photoemission and resonant inelastic scattering. We found that one type of Ti 3d interface carriers, which give rise to the 2DES are located within three unit cells from the n-type interface in the SrTiO3
layer. Unexpectedly, another type of interface carriers, which are polarity-induced Ti-on-Al antisite defects, reside in the first three unit cells of the opposing LaAlO3 layer (∼10 Å). Our findings provide a microscopic picture of how the localized and mobile Ti 3d interface carriers distribute across the interface and suggest that the 2DES and 2D magnetism at the LaAlO3/SrTiO3 interface have disparate explanations as originating from different types of interface carriers.
Indexed by:Journal paper
Volume:4
Issue:11
Page Number:115002
Translation or Not:no
Date of Publication:2020-11-11
Included Journals:SCI
Links to published journals:https://link.aps.org/doi/10.1103/PhysRevMaterials.4.115002
First Author:Lin, Shih-Chieh
Correspondence Author:Kuo, Cheng-Tai
All the Authors:Shao, Yu-Cheng,Chuang, Yi-De,Geessinck, Jaap,Huijben, Mark,Rueff, Jean-Pascal,Graff, Ismael L.,Conti, Giuseppina,Peng, Yingying,Bostwick, Aaron,Rotenberg, Eli,Gullikson, Eric,Slavomír Nemšák,Arturas Vailionis,Gauquelin, Nicolas,Verbeeck, Johan,Ghiringhelli, Giacomo,Claus M. Schneider,,Charles S. Fadley
Date of Publication:2020-11-11