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 meta...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.展开更多
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)
文摘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.