标题：Stability and electronic structure studies of LaAlO3/SrTiO3 (110) heterostructures
作者机构：[Du, Y.-L] School of Physics, State Key Laboratory of Crystal Materials, Shandong University, Jinan 250100, China, College of Science and Technology, 更多
通讯作者地址：[Li, JC]Shandong Univ, State Key Lab Crystal Mat, Sch Phys, Jinan 250100, Peoples R China.
关键词：two-dimensional electron gas;LaAlO3/SrTiO3(110) interface;magnetic interface
摘要：The first-principles calculations are employed to investigate the stability, magnetic, and electrical properties of the oxide heterostructure of LaAlO3/SrTiO3 (110). By comparing their interface energies, it is obtained that the buckled interface is more stable than the abrupt interface. This result is consistent with experimental observation. At the interface of LaAlO3/SrTiO3 (110) heterostructure, the Ti-O octahedron distortions cause the Ti t(2g) orbitals to split into the twofold degenerate d(xz)/d(yz) and nondegenerate d(xy) orbitals. The former has higher energy than the latter. The partly filled two-fold degenerate t(2g) orbitals are the origin of two-dimensional electron gas, which is confined at the interface. Lattice mismatch between LaAlO3 and SrTiO3 leads to ferroelectric-like lattice distortions at the interface, and this is the origin of spin-splitting of Ti 3d electrons. Hence the magnetism appears at the interface of LaAlO3/SrTiO3 (110).