Metal-induced charge transfer, structural distortion, and orbital order in SrTiO3 thin films

被引：10

作者：

Lee, Jaekwang ^{[1
]}

Lin, Chungwei ^{[1
]}

Demkov, Alexander A. ^{[1
]}

机构：

[1] Univ Texas Austin, Dept Phys, Austin, TX 78712 USA

来源：

PHYSICAL REVIEW B | 2013年 / 87卷 / 16期

基金：

美国国家科学基金会;

关键词：

AB-INITIO; CESIUM ADSORPTION; PHASE-TRANSITION; BARRIER HEIGHTS; WORK FUNCTION; SURFACE; ENERGY; OXIDE; 1ST-PRINCIPLES; INTERFACE;

D O I：

10.1103/PhysRevB.87.165103

中图分类号：

T [工业技术];

学科分类号：

08 ;

摘要：

The atomic and electronic properties of the Cs/SrTiO3 heterostructure are investigated using density functional theory. Our results suggest that an antiferrodistortive (AFD) or a ferroelectric (FE) like distortion could be induced in SrTiO3 (STO) by a Cs layer, depending on the interface bonding geometry between the metal and the oxide. Furthermore, while the AFD distortion extends throughout the STO region, the FE-like distortion decays within two layers of STO. Independent of the interface geometry, we find a large e(g) orbital splitting (orbital order) around the interface, leading to an eg-based two-dimensional electron gas (2DEG) confined within the two layers of STO, which is fundamentally different from the conventional t(2g)-based 2DEG in this material. This unique feature can be understood in terms of the local orbital mixing at the interface. We discuss the relation between the orbital order and structural distortion. DOI: 10.1103/PhysRevB.87.165103

引用

页数：7

共 45 条

[1] Cesium under pressure: First-principles calculation of the bcc-to-fcc phase transition [J].