Conductivity and band alignment of LaCrO_3/SrTiO_3(111) heterostructure  

作　　者：Yan-Peng Hong Xin-Xin Wang Guo-Liang Qu Cheng-Jian Li Hong-Xia Xue Ke-Jian Liu Yong-Chun Li Chang-Min Xiong Rui-Fen Dou Lin He Jia-Cai Nie 洪彦鹏;王欣欣;曲国良;厉承剑;薛红霞;刘科践;李永春;熊昌民;窦瑞芬;何林;聂家财(Department of Physics,Beijing Normal University)

机构地区：Department of Physics, Beijing Normal University, Beijing 100875, China

出　　处：《Chinese Physics B》2018年第4期401-407,共7页中国物理B（英文版）

基　　金：Project supported by the National Natural Science Foundation of China(Grant Nos.11674031,11474022 11474024,11422430,and 11374035);the National Basic Research Program of China(Grant Nos.2014CB920903,2013CB921701,and 2013CBA01603)

摘　　要：In this work,we investigate the electrical transport property and electronic structure of oxide heterostructure LaCrO3/SrTiO3（111）.The interface grown under relatively low oxygen partial pressure is found to be metallic with a conducting critical thickness of 11 unit cells of LaCrO3.This criticality is also observed by x-ray photoelectron spectroscopy,in which the Ti^3＋ signal intensity at the spectrum edge of the Ti-2p（3/2） core level increases rapidly when the critical thickness is reached.The variations of the valence band offset and full width at half maximum of the core-level spectrum with LaCrO3 thickness suggest that the built-in fields exist both in LaCrO3 and in SrTiO3.Two possible origins are proposed：the charge transfer from LaCrO3 and the formation of a quantum well in SrTiO3.Our results shed light on the understanding of the doping mechanism at the polar/non-polar oxide interface.Moreover,due to the interesting lattice and spin structure of LCO in the（111） direction,our work provides a basis for further exploring the novel topological quantum phenomena in this system.In this work,we investigate the electrical transport property and electronic structure of oxide heterostructure LaCrO3/SrTiO3（111）.The interface grown under relatively low oxygen partial pressure is found to be metallic with a conducting critical thickness of 11 unit cells of LaCrO3.This criticality is also observed by x-ray photoelectron spectroscopy,in which the Ti^3＋ signal intensity at the spectrum edge of the Ti-2p（3/2） core level increases rapidly when the critical thickness is reached.The variations of the valence band offset and full width at half maximum of the core-level spectrum with LaCrO3 thickness suggest that the built-in fields exist both in LaCrO3 and in SrTiO3.Two possible origins are proposed：the charge transfer from LaCrO3 and the formation of a quantum well in SrTiO3.Our results shed light on the understanding of the doping mechanism at the polar/non-polar oxide interface.Moreover,due to the interesting lattice and spin structure of LCO in the（111） direction,our work provides a basis for further exploring the novel topological quantum phenomena in this system.

关 键 词：oxide heterostructure LaCrO3/SrTiO3 （111） x-ray photoelectron spectroscopy electronic structure 

分 类 号：O48[理学—固体物理]