High-mobility spin-polarized two-dimensional electron gas at the interface of LaTiO_(3)/SrTiO_(3)(110)heterostructures

作     者：Zhao-Cai Wang Zheng-Nan Li Shuang-Shuang Li Weiyao Zhao Ren-Kui Zheng 

作者机构：School of Physics and Materials ScienceNanchang UniversityNanchang 330031China Department of Materials Science&EngineeringMonash UniversityClayton VIC 3800Australia School of Physics and Materials ScienceGuangzhou UniversityGuangzhou 510006China 

出 版 物：《Frontiers of physics》 (物理学前沿（英文版）)

年 卷 期：2024年第19卷第5期

页      面：129-141页

核心收录：

学科分类：080805[工学-电工理论与新技术] 080904[工学-电磁场与微波技术] 0808[工学-电气工程] 0809[工学-电子科学与技术（可授工学、理学学位）] 08[工学] 

基　　金：supported by the National Natural Science Foundation of China(Grant No.11974155) the Natural Science Foundation of Guangdong Province(Grant No.2022A1515010583) Bureau of Education of Guangzhou Municipality(Grant No.202255464) 

主　　题：two-dimensional electron gas heterostructure spin polarization electronic transport interface 

摘      要：High-quality antiferromagnetic Mott insulator thin films of LaTiO_(3)(LTO)were epitaxially grown onto SrTiO_(3)(STO)(110)substrates using the pulsed laser *** LTO/STO heterostructures are not only highly conducting and ferromagnetic,but also show Kondo effect,Shubnikov‒de Haas(SdH)oscillations with a nonzero Berry phase ofπ,and lowfield hysteretic negative magnetoresistance(MR).Angle-dependent SdH oscillations and a calculation of the thickness of the interfacial conducting layer indicate the formation of a 4-nm high mobility two-dimensional electron gas(2DEG)layer at the ***,an amazingly large lowfield negative MR of∼61.8%is observed at 1.8 K and 200 Oe,which is approximately one to two orders of magnitude larger than those observed in other spin-polarized 2DEG oxide *** these results demonstrate that the 2DEG is spin-polarized and the 4-nm interfacial layer is ferromagnetic,which are attributed to the presence of magnetic Ti^(3+)ions due to interfacial oxygen vacancies and the diffusion of La^(3+)ions into the STO *** localized Ti^(3+)magnetic moments couple to high mobility itinerant electrons under magnetic fields,giving rise to the observed lowfield *** work demonstrates the great potential of antiferromagnetic titanate oxide interface for designing spin-polarized 2DEG and spintronic devices.